Question

a) (9-x) × (9+x)
b) (4x+2y²) × (4x-2y²)
c) (5xy-8x) × ( 5xy+8x)


por favor, me ajudem!!​

Answer 1

Resposta:

$(9 - x)(9 + x) \\ 49 - 9x + 9x - {x}^{2} \\ 49 - {x }^{2} = 0 \\ 49 = {x}^{2} \\ x = \sqrt{49} \\ x = 7$

b)