Question

решите уравнения 1)30(1.8-у)^2+20(у+1.8)(у-1.8)=50у^2+140.4
дам 30 баллов

Answer 1

$30(1.8 - y) {}^{2} + 20(y + 1.8)(y - 1.8) = 50y {}^{2} + 140.4 \\ 97.2- 108y + 30y {}^{2} + 20y {}^{2} - 64.8 - 50y {}^{2} - 140.4 = 0 \\ - 108y - 108 = 0 \\ - 108y = 108 \\ y = - 1$