Question

Use completing the square to solve the equation x2 - 10x = -8.Which equation is used in the process?
x2- 10x + 25 = 17
x2- 10x + 25 = -8
x2- 10x - 25 = -33

Answer 1

well the 1st step is to add half the coefficient of x then square it to both sides

so the coefficient is -10 -10/2 = -5 and(-5)^2 = 25

so add 25 to both sides of the equation

then write the equation as

(x -5)^2 = 17

take the square root of both sides

then add 5

so

\[x = 5 + \sqrt{17}\]