Question

In the quadratic equation x2 - 8x + a = 0; what is the value, a, in order to form a perfect square?

Answer 1

16

Explanation:

(x - y)² = x² - 2xy + y²

x = x and y = a

2xy = 8x

2*x*a = 8x

a =
`(8x)/(2x)`

a = 4

a² = 16