7y = 14
y=2
5x+4y=3
5x+8=3
5x=-5
x = -1
Ответ: (-1;2)
X³+x²-xу²-y²=(х³+х²)-(ху²+у²)=х²(х+1)-у²(х+1)=
=(х+1)(х²-у²)=(х+1)(х-у)(х+у)
8^7 + 4^11 = (2^3)^7 + (2^2)^11 = 2^21 + 2^22 = 2^21 + 2*2^21 = (2 + 4)^21 = 6<span>^21; 6/3
</span>5^7 + (5^2)^3 = 5^7 + 5^6 = (25 + 5)^6 = 30<span>^6; 30/30
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