Answer:
c = 25
Step-by-step explanation:
Given this quadratic expression.
x² – 10x + c = 0
We are to find the value c that will make the expression a perfect square'
Using the completing the square method
Add the square of the half of coefficient of x
Coefficient of x = -10
Half of -10 = 1/2(-10) = -5
Square of -5 = (-5)^2 = 25
Hence the value of c to complete the expression is 25
