Solve the Fraction Equation: Balance −8 + X/3 = X + 4/9

Question

Solve for X:

8+x3=x+49 \frac{-8+x}{3}=\frac{x+4}{9}

Video Solution

Solution Steps

00:00 Solve
00:03 We want to isolate the unknown X
00:07 Multiply by both denominators to eliminate fractions
00:19 Simplify as much as possible
00:41 Open parentheses properly, multiply by each factor
00:48 Arrange the equation so that one side has only the unknown X
01:08 Isolate the unknown X
01:16 And this is the solution to the problem

Step-by-Step Solution

To solve for x x in the equation 8+x3=x+49\frac{-8+x}{3}=\frac{x+4}{9}, we'll follow these steps:

  • Step 1: Eliminate the fractions by finding a common denominator.
  • Step 2: Simplify the resulting equation.
  • Step 3: Isolate x x to solve the equation.

Let's proceed step by step:

Step 1: The equation 8+x3=x+49\frac{-8+x}{3}=\frac{x+4}{9} contains denominators 3 and 9. The least common denominator (LCD) is 9. To eliminate the fractions, multiply every term of the equation by 9.

9×8+x3=9×x+499 \times \frac{-8+x}{3} = 9 \times \frac{x+4}{9}

Simplifying, we have:

3(8+x)=x+43(-8 + x) = x + 4

Step 2: Distribute the 3 on the left side:

3×8+3×x=x+43 \times -8 + 3 \times x = x + 4

This simplifies to:

24+3x=x+4-24 + 3x = x + 4

Step 3: Isolate x x . First, subtract x x from both sides of the equation:

24+3xx=x+4x-24 + 3x - x = x + 4 - x

This simplifies to:

24+2x=4-24 + 2x = 4

Next, add 24 to both sides to further isolate x x :

24+24+2x=4+24-24 + 24 + 2x = 4 + 24

This simplifies to:

2x=282x = 28

Finally, divide both sides by 2 to solve for x x :

x=282x = \frac{28}{2}

Simplifying this gives:

x=14x = 14

Therefore, the solution to the equation is x=14 x = 14 .

Answer

14 14