Question

Find all solutions of the equation 4x^2−144=0 by factoring the left hand side and using the zero factor property.

Answer 1

x = ±6

Explanation:

The left side is the difference of squares, so factors accordingly:

(2x -12)(2x +12) = 0

The zero factor property tells you the product will be zero when one or more factors is zero.

2x -12 = 0

x -6 = 0 . . . . divide by 2

x = 6 . . . . . . one solution to the equation

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2x +12 = 0

x + 6 = 0 . . . . divide by 2

x = -6 . . . . . . . the other solution to the equation