4x -2y = -9
3x - 3y = -6 | /3
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4x - 2y = -9
x - y = -2
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4 * (-2 + y) - 2y = -9
x = -2 + y
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4 * (-2 + y) - 2y = -9
-8 + 4y - 2y = -9
2y = -9 + 8
y = -1/2
y = -0.5
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x = -2 + (-0.5) = - 2 - 0.5 = -2.5
Ответ: ( - 2,5 ; -0,5)
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-6x*4y*(-27)=648ху
-2,5a*0,04c=-0,1ас
5xz*3yz=15zyz^2
3a +5 -(2a+6) +4a=3a+5-2a-6=a-1
-3*(2m+n) +(7m-n)=-6m-3n+7m-n=m-4n
4x-(5x-(1-x))=4x-(5x-1+x)=4x-(6x-1) =4x-6x+1=1-2x
tg a*cos a=(sin a/cos a)*cos a=sin a
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