SOLUTION: what is the solution to (x-1) (X-2)=30

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Question 503491: what is the solution to (x-1) (X-2)=30
Found 2 solutions by oberobic, Maths68:
Answer by oberobic(2304) About Me  (Show Source):
You can put this solution on YOUR website!
(x-1)(x-2) = 30
expand
x^2 -1x -2x + 2 = 30
collect terms
x^2 -3x -28 = 0
factor
(x-7)(x+4) = 0
so
x=7 or x=-4.
.
graph%28500%2C500%2C-10%2C10%2C-35%2C35%2Cx%2Ax-3%2Ax-28%29

Answer by Maths68(1474) About Me  (Show Source):
You can put this solution on YOUR website!
(x-1) (x-2)=30
x^2-2x-x+2=30
x^2-3x+2=30
x^2-3x+2-30=0
x^2-3x-28=0
x^2-7x+4x-28=0
x(x-7)+4(x-7)=0
(x-7)(x+4)=0
(x-7)=0 or (x+4)=0
x-7=0 or x+4=0
x=7 or x=-4
Check x=7
(x-1) (x-2)=30
(7-1)(7-2)=30
(6)(5)=30
30-30
x=-4
(x-1)(x-2)=30
(-4-1)(-4-2)=30
(-5)(-6)=30
30=30