Question

qual e o valor das expressoes: (5×-6)²-(5×+4)·(5×-4)

Answer 1

$(5x-6)^2-(5x+4)*(5x-4) \\ \\ (5x-6)*(5x-6) - (5x+4)*(5x-4) \\ \\ 25x^2 -30x -30x + 36 - 25x^2 +20x - 20x +16 = 0 \\ \\ -60x +52 = 0 *(-1) => 60x - 52 = 0 \\ \\ 60x = -52 \\ \\ x= \frac{-52}{60} \\ \\ x= \frac{-52}{60} \frac{\div}{\div} \frac{4}{4} = -\frac{13}{15}$

S = $-\frac{13}{15}$