PERFECT SQUARES 1

If Fx² - 30x + 25 is a perfect square, find f

Solution

a = f, b = 30, c = 25.

b² = 4ac

(-30)² = 4 x f x 25

900 = 100f   (since -30 x -30 = +900)

900 = 100f (Divide by 100 on both sides)

100 = 100 

f = 9   

Hence f= 9

TRY THIS.........................................

If Fx² -20x + 4 is a perfect square, find f