Examples with solutions for Square Root Quotient Property: Solving the equation

Exercise #1

Solve the following equation:

644=2x \frac{\sqrt{64}}{\sqrt{4}}=2x

Video Solution

Step-by-Step Solution

Introduction:

We will address the following two laws of exponents:

a. Definition of root as an exponent:

an=a1n \sqrt[n]{a}=a^{\frac{1}{n}}

b. The law of exponents for an exponent applied to terms in parentheses:

(ab)n=anbn (\frac{a}{b})^n=\frac{a^n}{b^n}

Note:

By combining the two laws of exponents mentioned in a (in the first and third stages below) and b (in the second stage below), we can derive another new rule:

abn=(ab)1n=a1nb1n=anbnabn=anbn \sqrt[n]{\frac{a}{b}}=\\ (\frac{a}{b})^{\frac{1}{n}}=\\ \frac{a^{\frac{1}{n}}}{ b^{\frac{1}{n}}}=\\ \frac{\sqrt[n]{a}}{ \sqrt[n]{ b}}\\ \downarrow\\ \boxed{ \sqrt[n]{\frac{a}{b}}=\frac{\sqrt[n]{a}}{ \sqrt[n]{ b}}}

Specifically for the fourth root we obtain the following:

ab=ab \boxed{ \sqrt{\frac{a}{ b}}=\frac{\sqrt{a}}{\sqrt{ b}} }

Therefore, we can proceed to solve the problem:

644=2x \frac{\sqrt{64}}{\sqrt{4}}=2x

Let's start by simplifying the expression on the left side, using the new rule that we studied in the introduction:

ab=ab \boxed{ \sqrt{\frac{a}{ b}}=\frac{\sqrt{a}}{\sqrt{ b}} }

( However this time in the opposite direction, meaning we'll insert the product of roots as a product of terms under the same root) Then we'll perform the multiplication under the root:

644=2x644=2x16=2x4=2x \frac{\sqrt{64}}{\sqrt{4}}=2x \\ \sqrt{\frac{64}{4}}=2x \\ \sqrt{16}=2x \\ 4=2x \\ In the final stage, we used the known fourth root of the number 16,

After simplifying the expression on the left side, to isolate the unknown, we'll divide both sides of the equation by its coefficient:

4=2x/:22=xx=2 4=2x\hspace{6pt}\text{/}:2 \\ 2=x \\ \downarrow\\ \boxed{x=2}

Let's summarize the solution of the equation:

644=2x16=2x4=2xx=2 \frac{\sqrt{64}}{\sqrt{4}}=2x \\ \sqrt{16}=2x \\ 4=2x \\ \downarrow\\ \boxed{x=2}

Therefore, the correct answer is answer b.

Answer

2

Exercise #2

Solve for x:

6x=36 \sqrt{6}x=\sqrt{36}

Video Solution

Step-by-Step Solution

To solve the equation 6x=36 \sqrt{6}x = \sqrt{36} , we will proceed with the following steps:

  • Step 1: Simplify the square root on the right-hand side.
    36=6\sqrt{36} = 6.
  • Step 2: Substitute the simplified value back into the equation to obtain:
    6x=6\sqrt{6}x = 6.
  • Step 3: Solve for x x by isolating the variable. Divide both sides by 6\sqrt{6}:
    x=66 x = \frac{6}{\sqrt{6}} .
  • Step 4: Simplify the fraction:
    Multiply the numerator and denominator by 6\sqrt{6}:
    x=6×66×6=666=6 x = \frac{6 \times \sqrt{6}}{\sqrt{6} \times \sqrt{6}} = \frac{6 \sqrt{6}}{6} = \sqrt{6} .

Therefore, the solution to the equation is x=6 x = \sqrt{6} .

Answer

6 \sqrt{6}

Exercise #3

Solve the following equation:

90x=3 \frac{\sqrt{90}}{\sqrt{x}}=3

Video Solution

Step-by-Step Solution

To solve this problem, we'll apply the properties of square roots and some straightforward algebraic techniques:

Step 1: Recall the equation given is:

90x=3 \frac{\sqrt{90}}{\sqrt{x}} = 3

Use the property of the square root quotient:

90x=3 \sqrt{\frac{90}{x}} = 3

Step 2: To eliminate the square root, square both sides of the equation:

(90x)2=32 \left(\sqrt{\frac{90}{x}}\right)^2 = 3^2

Thus, we have:

90x=9 \frac{90}{x} = 9

Step 3: Solve for xx by performing algebraic manipulation:

Multiply both sides by xx to remove the fraction:

90=9x 90 = 9x

Divide both sides by 9 to isolate xx:

x=909 x = \frac{90}{9}

Simplifying, we find:

x=10 x = 10

Therefore, the solution to the equation is x=10 x = 10 .

Answer

10

Exercise #4

Solve the following equation:

50x=5 \frac{\sqrt{50}}{\sqrt{x}}=5

Video Solution

Step-by-Step Solution

To solve the given equation, 50x=5\frac{\sqrt{50}}{\sqrt{x}} = 5, we will follow these steps:

  • Step 1: Multiply both sides by x\sqrt{x} to isolate x\sqrt{x}:
    50=5x\sqrt{50} = 5\sqrt{x}.
  • Step 2: Divide both sides by 5 to solve for x\sqrt{x}:
    x=505\sqrt{x} = \frac{\sqrt{50}}{5}.
  • Step 3: Simplify 505\frac{\sqrt{50}}{5}:
    50=25×2=252=52\sqrt{50} = \sqrt{25 \times 2} = \sqrt{25}\sqrt{2} = 5\sqrt{2}. Thus, 525=2\frac{5\sqrt{2}}{5} = \sqrt{2}.
  • Step 4: Square both sides to solve for xx:
    x=(2)2=2x = (\sqrt{2})^2 = 2.

Now, compare with the provided choices:
Choice b is 4\sqrt{4}, which simplifies to 2.
Choice c is 2. Both represent the correct answer.

Therefore, the correct answer is Answers b and c.

Answer

Answers b and c

Exercise #5

Solve for x:

205x=225 \frac{\sqrt{20}\cdot\sqrt{5}}{x}=2\cdot\sqrt{25}

Video Solution

Step-by-Step Solution

To solve the equation \<205x=225\frac{\sqrt{20}\cdot\sqrt{5}}{x} = 2\cdot\sqrt{25}\>, follow these steps:

  • Step 1: Simplify the left-hand side.
    - Use the product rule for roots: 205=205=100\sqrt{20} \cdot \sqrt{5} = \sqrt{20 \cdot 5} = \sqrt{100}.
  • Step 2: Simplify 100\sqrt{100} to get 10\.
  • Step 3: Substitute and simplify the equation:
    \(\frac{10}{x} = 2 \cdot \sqrt{25}.
  • Step 4: Simplify the right-hand side:
    25=5\sqrt{25} = 5 so 25=102 \cdot 5 = 10.
  • Step 5: Equate both sides:
    10x=10\frac{10}{x} = 10.
  • Step 6: Solve for xx:
    Multiply both sides by xx, then divide by 10:
    10=10x10 = 10x produces x=1x = 1.

Therefore, the solution to the problem is x=1\boldsymbol{x = 1}.

Answer

1 1

Exercise #6

Solve for x:

8422=x2 \frac{\sqrt{8}\cdot\sqrt{4}\cdot\sqrt{2}}{\sqrt{2}}=\sqrt{x^2}

Video Solution

Step-by-Step Solution

To solve this problem, we'll follow these steps:

  • Simplify the expression 842\sqrt{8}\cdot\sqrt{4}\cdot\sqrt{2}.
  • Divide this product by 2\sqrt{2}.
  • Set the result equal to x2\sqrt{x^2} and solve for x x .

Now, let's work through each step:

Step 1: First, simplify the product under the square root:

842=842\sqrt{8}\cdot\sqrt{4}\cdot\sqrt{2} = \sqrt{8\cdot4\cdot2}.

This simplifies to:

64\sqrt{64}, because 842=648 \cdot 4 \cdot 2 = 64.

Step 2: Now, divide by 2\sqrt{2}:

642=642=32\frac{\sqrt{64}}{\sqrt{2}} = \sqrt{\frac{64}{2}} = \sqrt{32}.

Step 3: Equate this to x2\sqrt{x^2}:

32=x2\sqrt{32} = \sqrt{x^2}.

This implies x=32 |x| = \sqrt{32} , giving us two possible solutions: x=32 x = \sqrt{32} and x=32 x = -\sqrt{32} .

Since the simplification naturally leads to positive expressions, we find:

The solution is x=32 x = \sqrt{32} .

Answer

x=32 x=\sqrt{32}

Exercise #7

Solve the following equation:

4510=x \frac{\sqrt{4}\cdot\sqrt{5}}{\sqrt{10}}=x

Video Solution

Step-by-Step Solution

Introduction:

We will address the following three laws of exponents:

a. Definition of root as an exponent:

an=a1n \sqrt[n]{a}=a^{\frac{1}{n}}

b. The law of exponents for an exponent applied to a product in parentheses:

(ab)n=anbn (a\cdot b)^n=a^n\cdot b^n

c. The law of exponents for an exponent applied to a quotient in parentheses:

(ab)n=anbn (\frac{a}{b})^n=\frac{a^n}{b^n}

Note:

(1). By combining the two laws of exponents mentioned in a (in the first and third steps ) and b (in the second step ), we can obtain a new rule:

abn=(ab)1n=a1nb1n=anbnabn=anbn \sqrt[n]{a\cdot b}=\\ (a\cdot b)^{\frac{1}{n}}=\\ a^{\frac{1}{n}}\cdot b^{\frac{1}{n}}=\\ \sqrt[n]{a}\cdot \sqrt[n]{ b}\\ \downarrow\\ \boxed{\sqrt[n]{a\cdot b}=\sqrt[n]{a}\cdot \sqrt[n]{ b}}

Specifically for the fourth root we obtain the following::

ab=ab \boxed{ \sqrt{a\cdot b}=\sqrt{a}\cdot \sqrt{ b}}

(2). Similarly, note that by combining the two laws of exponents mentioned in a (in the first and third steps later) and c (in the second step later), we can obtain another new rule:

abn=(ab)1n=a1nb1n=anbnabn=anbn \sqrt[n]{\frac{a}{b}}=\\ (\frac{a}{b})^{\frac{1}{n}}=\\ \frac{a^{\frac{1}{n}}}{ b^{\frac{1}{n}}}=\\ \frac{\sqrt[n]{a}}{ \sqrt[n]{ b}}\\ \downarrow\\ \boxed{ \sqrt[n]{\frac{a}{b}}=\frac{\sqrt[n]{a}}{ \sqrt[n]{ b}}}

Specifically for the fourth root we obtain the following:

ab=ab \boxed{ \sqrt{\frac{a}{ b}}=\frac{\sqrt{a}}{\sqrt{ b}} }

Therefore, in solving the problem, meaning - in simplifying the given expression, we will apply the two new rules that we received in the introduction:

(1).

ab=ab \boxed{ \sqrt{a\cdot b}=\sqrt{a}\cdot \sqrt{ b}}

(2).

ab=ab \boxed{ \sqrt{\frac{a}{ b}}=\frac{\sqrt{a}}{\sqrt{ b}} }

We will start by simplifying the expression in the numerator using the rule that we examined in the introduction (1) (however this time in the opposite direction, meaning we will insert the product of roots as a product of terms under the same root) Then we will proceed to perform the multiplication under the root in the numerator:

4510=4510=2010= \frac{\sqrt{4}\cdot\sqrt{5}}{\sqrt{10}}= \\ \frac{\sqrt{4\cdot5}}{\sqrt{10}}= \\ \frac{\sqrt{20}}{\sqrt{10}}= \\ We will then simplify the fraction, using the second rule that we examined in the introduction (2) (once again in the opposite direction, meaning we will insert the quotient of roots as a quotient of terms under the same root) Then we will proceed to reduce the fraction under the root:

2010=2010=2 \frac{\sqrt{20}}{\sqrt{10}}= \\ \sqrt{\frac{20}{10}}=\\ \boxed{\sqrt{2}}

Summarize the process of simplifying the expression in the problem:

4510=2010=2 \frac{\sqrt{4}\cdot\sqrt{5}}{\sqrt{10}}= \\ \frac{\sqrt{20}}{\sqrt{10}}= \\ \boxed{\sqrt{2}}

Therefore, the correct answer is answer c.

Answer

2 \sqrt{2}

Exercise #8

Solve for x:

4525=2x \frac{\sqrt{4}\cdot\sqrt{5}}{\sqrt{25}}=2x

Video Solution

Step-by-Step Solution

To solve 4525=2x\frac{\sqrt{4} \cdot \sqrt{5}}{\sqrt{25}} = 2x, we follow these steps:

  • Simplify 4\sqrt{4}: The square root of 4 is 2.
  • Simplify 5\sqrt{5}: 5\sqrt{5} remains 5\sqrt{5}.
  • Simplify 25\sqrt{25}: The square root of 25 is 5.
  • Substitute these values back: 255=2x\frac{2 \cdot \sqrt{5}}{5} = 2x.
  • Write the expression: 255=2x\frac{2\sqrt{5}}{5} = 2x.
  • Divide both sides by 2 to solve for xx:
  • x=2552=55 x = \frac{2\sqrt{5}}{5 \cdot 2} = \frac{\sqrt{5}}{5}

The simplified expression for 5\sqrt{5} is equivalent to 2010\frac{\sqrt{20}}{10}, using 5=202\sqrt{5} = \frac{\sqrt{20}}{2} since 20=25\sqrt{20} = 2\sqrt{5}.

Therefore, the solution to the problem is 2010\boxed{\frac{\sqrt{20}}{10}}.

Answer

x=2010 x=\frac{\sqrt{20}}{10}

Exercise #9

Solve for x:

2416=x8 \frac{\sqrt{2}\cdot\sqrt{4}}{\sqrt{16}}=\frac{x}{\sqrt{8}}

Video Solution

Step-by-Step Solution

Let's solve the equation step by step:

  • Step 1: Simplify the left side of the equation
    We are given 2416 \frac{\sqrt{2}\cdot\sqrt{4}}{\sqrt{16}} . Start by simplifying each square root:
    • 2 \sqrt{2} remains as it is.
    • 4=2 \sqrt{4} = 2 because 4=22 4 = 2^2 .
    • 16=4 \sqrt{16} = 4 because 16=42 16 = 4^2 .
    Substitute these into the initial expression: 224=224 \frac{\sqrt{2} \cdot 2}{4} = \frac{2\sqrt{2}}{4} .
  • Step 2: Simplify the expression
    The expression 224 \frac{2\sqrt{2}}{4} simplifies to 22 \frac{\sqrt{2}}{2} .
  • Step 3: Equate to the right side
    Set this equal to the right side: 22=x8 \frac{\sqrt{2}}{2} = \frac{x}{\sqrt{8}} .
  • Step 4: Cross-multiply to solve for x x
    Cross-multiplying gives x2=28 x \cdot 2 = \sqrt{2} \cdot \sqrt{8} . Simplify the right side:
    • 8=42=42=22 \sqrt{8} = \sqrt{4 \cdot 2} = \sqrt{4} \cdot \sqrt{2} = 2\sqrt{2}
    • So, 28=222=2(22)=22=4 \sqrt{2} \cdot \sqrt{8} = \sqrt{2} \cdot 2\sqrt{2} = 2 \cdot (\sqrt{2} \cdot \sqrt{2}) = 2 \cdot 2 = 4
    • The equation becomes 2x=4 2x = 4 .
    • Solving for x x , divide both sides by 2: x=42=2 x = \frac{4}{2} = 2 .

Therefore, the solution to the problem is x=2 x = 2 .

Answer

2 2