Question

(3x +7)square – 8 4x = (3x – 7)square ​

Answer 1

Answer:

${(3x + 7)}^{2} - 84x \\ = {(3x)}^{2} + {7}^{2} + 2 \times 3x \times 7 - 84x \\ = 9 {x}^{2} + 49 + 42x - 84x \\ = 9 {x}^{2} + 49 - 42x \\ = {(3x)}^{2} + {7}^{2} - 2 \times 3x \times 7 \\ = {(3x - 7)}^{2}$

Answer 2

(3x +7)² – 84x

9x² + 49 + 42x - 84x

9x² + 49 - 42x

(3x - 7)²