Решите уравнение:
2[tex] x^{2} + 3x = 2 x^{2} + 21[/tex]
[tex](3x+1)(4x-5)=12 x^{2} - 13x +1[/tex]
Упростить выражение:
[tex](2x-3)(3x+7)-(x-5)=12 x^{2} -13x+1 [/tex] при x = 11

2x^2+3x = 2x^2+213x = 21x = 7(3x+1)(4x-5) = 12x^2-13x+112x^2-11x-5 = 12x^2-13x+12x = 6x = 3(2x-3)(3x+7)-(x-5) = 12x^2-13x+16x^2+14x-9x-21-x+5 = 12x^2-13x+1-6x^2+17x = 17x(17-6x) = 17