SOLUTION: Solve the equation x^2=-5x+24 I don't know what I am doing wrong :(

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Question 350050: Solve the equation
x^2=-5x+24
I don't know what I am doing wrong :(

Answer by Jk22(389) About Me  (Show Source):
You can put this solution on YOUR website!
x^2=-5x+24 |put all on Lhs : +5x-24 on both side

x^2+5x-24=0 | use Viete's method : (x+a)(x+b)=x^2+(a+b)x+ab, here a=8, b=-3

hence a+b=8-3=5, ab=8*(-3)=-24

(x+8)(x-3)=0, hence x=-8, or x=3

Verification :
(-8)^2=64, -5*(-8)+24=40+24=64
3^2=9, -5*3+24=-15+24=9