(х^2 - 5x) + (5х – 2x^2)=х²-5х+5х-2х²= - х²
(в^2 - в+ 7) — (в^2 +в+ 8) = b²-b+7-b²-b-8= - 2b-1
(а^2 - 5aв) — (7- Зав) + (2ав - а^2) = =a²-5ab-7+3ab+2ab-a²= - 7
(t²+2t-3)-(t²-3t+4)=t-1
t²+2t-3 - t²+3t-4=t-1
5t-7=t-1
4t=6
t=6/4=3/2
(х^2 - 5x) + (5х – 2x^2)=х²-5х+5х-2х²= - х²
(в^2 - в+ 7) — (в^2 +в+ 8) = b²-b+7-b²-b-8= - 2b-1
(а^2 - 5aв) — (7- Зав) + (2ав - а^2) = =a²-5ab-7+3ab+2ab-a²= - 7
(t²+2t-3)-(t²-3t+4)=t-1
t²+2t-3 - t²+3t-4=t-1
5t-7=t-1
4t=6
t=6/4=3/2