Question

Follow the process of completing the square to solve x2 - 10x + 8 = 0.

What is the value of the constant that will be isolated on the right side of the equation in step 3?

1. -32
2. -12
3. -8

Answer 1

so whats the answer then?

Explanation:

Answer 2

Option 3. -8

Explanation:

we have

`x^(2) -10x+8=0`

Group terms that contain the same variable, and move the constant to the opposite side of the equation

`x^(2) -10x=-8`

Complete the square. Remember to balance the equation by adding the same constants to each side

`x^(2) -10x+25=-8+25` ----> the isolated constant right side is -8

`x^(2) -10x+25=17`

Rewrite as perfect squares

`(x-5)^(2)=17`

Square root both sides

`x-5=(+/-)√(17)`

`x=5(+/-)√(17)`