(x+7)² = x² + mx + 49 (x+7)(x+7) = x² + mx + 49 x² + 7x + 7x + 49 = x² + mx + 49 x² + 14x + 49 = x² + mx + 49 Subtract x² and 49 from both sides x² + 14x + 49 = x² + mx + 49 -x² -49 -x² -49 ----------------------------- 14x = mx Divide both sides by x 14 = m Edwin