Question

What value of g makes the equation true? (X-3)(x+5) = x2 +gx-15

Answer 1

g = 2

Explanation:

Use FOIL:

(a + b)(c + d) = ac+ ad + bc + bd

(x - 3)(x + 5) = (x)(x) + (x)(5) + (-3)(x) + (-3)(5)

= x² + 5x - 3x - 15 = x² + 2x - 15

(x - 3)(x + 5) = x² + gx - 15

therefore g = 2