Value

What is value?

Value in mathematics indicates how much something is worth numerically.

What is the value of the function?

The word value signifies how much the function "is worth" – that is, what the value of YY will be in the function when we substitute any number in XX.

What is a table of values?

The values in the value table indicate how much YY of a function will be worth when we substitute XX with different values.

What is absolute value?

The distance of the number in absolute value from the digit 00.
It will always be positive because it is a distance.

Practice Equation (+ what is the unknown)

Examples with solutions for Equation (+ what is the unknown)

Exercise #1

Calculate y given that x=2 x=2 and y=x y=x .

Video Solution

Step-by-Step Solution

We are given the equation y=x

We are also given the value of x, 

x=2

Therefore, we will insert the given value into the equation

y=2

And that's the solution!

Answer

2 2

Exercise #2

18= \left|18\right|=

Video Solution

Step-by-Step Solution

The "absolute value" can be viewed as the distance of a number from 0.
Therefore, the absolute value will not change the sign from negative to positive, it will always be positive.

Answer

18 18

Exercise #3

2= \left|-2\right|=

Video Solution

Step-by-Step Solution

When we have an exercise with these symbols || we understand that it refers to absolute value.

Absolute value does not relate to whether a number is positive or negative, but rather checks how far it is from zero.

In other words, 2 is 2 units away from zero, and -2 is also 2 units away from zero,

Therefore, absolute value essentially "zeroes out" the negativity of the number.

 

|-2| = 2

 

Answer

2 2

Exercise #4

Find a y when x=2

y=25x+2 y=\frac{2}{5}x+2

Video Solution

Step-by-Step Solution

In this exercise, we are given the value of X, so we will substitute it into the formula.

It's important to remember that between an unknown and a number there is a multiplication sign, therefore:

y=2/5*(2)+2

y=4/5+2

Let's convert to a decimal fraction:

y=0.8+2
y=2.8

And that's the solution!

Answer

2.8 2.8

Exercise #5

2x+75x12=8x+3 2x+7-5x-12=-8x+3

Video Solution

Step-by-Step Solution

To solve this exercise, we first need to identify that we have an equation with an unknown,

To solve such equations, the first step will be to arrange the equation so that on one side we have the numbers and on the other side the unknowns.

2X+75X12=8X+3 2X+7-5X-12=-8X+3

First, we'll move all unknowns to one side.
It's important to remember that when moving terms, the sign of the number changes (from negative to positive or vice versa).

2X+75X12+8X=3 2X+7-5X-12+8X=3

Now we'll do the same thing with the regular numbers.

2X5X+8X=37+12 2X-5X+8X=3-7+12

In the next step, we'll calculate the numbers according to the addition and subtraction signs.

2X5X=3X 2X-5X=-3X
3X+8X=5X -3X+8X=5X

37=4 3-7=-4
4+12=8 -4+12=8

5X=8 5X=8

At this stage, we want to get to a state where we have only one X X , not 5X 5X ,
so we'll divide both sides of the equation by the coefficient of the unknown (in this case - 5).

X=85 X={8\over5}

Answer

x=85 x=\frac{8}{5}

Exercise #6

Find a y when x=2 x=2

y=5x y=5x

Video Solution

Answer

10

Exercise #7

5x=0 5x=0

Video Solution

Answer

x=0 x=0

Exercise #8

5x=1 5x=1

What is the value of x?

Video Solution

Answer

x=15 x=\frac{1}{5}

Exercise #9

0.8= \left|0.8\right|=

Video Solution

Answer

0.8 0.8

Exercise #10

3= \left|3\right|=

Video Solution

Answer

3 3

Exercise #11

Find a y when x=2

y=12x y=\frac{1}{2}x

Video Solution

Answer

1 1

Exercise #12

Find a y when x=2

y=x8 y=x-8

Video Solution

Answer

6 -6

Exercise #13

14x+3=17 14x+3=17

x=? x=\text{?}

Video Solution

Answer

x=1 x=1

Exercise #14

18= −\left|-18\right|=

Video Solution

Answer

18 -18

Exercise #15

1914= \left|-19\frac{1}{4}\right|=

Video Solution

Answer

1914 19\frac{1}{4}