Question

12) 4+ x (x - 4 )= x ? calcule

Answer 1

4 + x ( x - 4 ) = x
4 + x² - 4x = x
x² - 4x - x + 4 = 0
x² - 5x + 4 = 0


delta = (-5)² - 4.1.4
delta = 25 - 16
delta = 9

x = -(-5) ± √9/2.1

x = 5 ± 3/2

x = 5 + 3/2 = 8/2 = 4

x = 5 - 3/2 = 2/2 = 1


s={ 4, 1 }