Решение
<span>5+2x-3(x-13) = 50
</span>5 + 2x - 3x + 39 = 50
- x = 50 - 44
- x = 6
x = - 6
(х*х*х*х)+(х*х*х)-х-1
Вроде так
1) = 6X^2 - 2X + 5 + 10X - 5X^2 = X^2 + 8X + 5
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2) = 6XY + 8Y - 2XY - 8Y + 1 = 4XY + 1
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