Question

72x elevado a 2 -30x-50 quando x=2

Answer 1

10x² + 72x - 64 = 0(:2)
5x² + 36x - 32 = 0
Delta = b² - 4ac
Delta = 1296 - 4(5)(-32)
Delta = 1296 + 640
Delta = 1936
X = (-b +- raiz delta) / 2a
X = (-36 +- 44) / 10
x' = (-36 + 44) / 10 = 8/10 = 4/5
x" = (-36 - 44) = -80/10 = -8