Question 386780
Solve for X

X^2 – 12  = -4x
add +4x
x^2+4x-12=0
x^2+6x-2x-12=0
x(x+6)-2(x+6)=0
(x+6)(x-2)=0
x=-6 OR x=2
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X^2 – 81 = 0
(x)^2-(9)^2
difference of two squares formula
a^2-b^2=(a+b)(a-b)
(x+9)(x-9)=0
x=+/- 9
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