Question

Solve the equation by completing the square. round to the nearest hundredth if necessary. x^2-6x=20

Answer 1

x^2-6x+(b/2)^2=20+(b/2)^2
x^2-6x+(6/2)^2=20+(6/2)^2
x^2-6x+(3)^2=20+(3)^2
x^2-6x+9=20+9
(x-3)^2=29
x-3=5.38 or -5.38
x=5.38+3 or -5.38+3
x=8.38 or -2.38

Answer 2

x^2 - 6x = 20
x^2 - 6x + 9 = 20 + 9
(x - 3)^2 = 29
x - 3 = (+-) sqrt 29
x = 3 (+-) sqrt 29
x = 3 (+-) 5.39

x = 3 + 5.39 = 8.39 <=
x = 3 - 5.39 = - 2.39 <=