РОЗВЯЗАТИ СИСТЕМИ МЕТОДОМ ПіДСТАНОВКИ Будь ласка

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РОЗВЯЗАТИ СИСТЕМИ МЕТОДОМ ПіДСТАНОВКИ Будь ласка

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\left \{ {{x=2y-6} \atop {y=\frac{18}{5} }} \right.Ответ:

Пошаговое объяснение:

a)\left \{ {{x+y=7} \atop {x+2y=11}} \right.

\left \{ {{x=7-y} \atop {7-y+2y=11}} \right.

\left \{ {{x=7-y} \atop {y=11-7}} \right.

\left \{ {{x=7-y} \atop {y=4}} \right.

\left \{ {{x=7-4} \atop {y=4}} \right.

\left \{ {{x=3} \atop {y=4}} \right.

b)\left \{ {{x-2y=11} \atop {-2x+y=-4}} \right.

\left \{ {{x=11+2y} \atop {-2(11+2y)+y=-4}} \right.

\left \{ {{x=11+2y} \atop {-22-4y+y=-4}} \right.

\left \{ {{x=11+2y} \atop {-3y=-4+22}} \right.

\left \{ {{x=11+2y} \atop {-3y=18}} \right.

\left \{ {{x=11+2y} \atop {y=-\frac{18}{3} }} \right.

\left \{ {{x=11+2y} \atop {y=-6}} \right.

\left \{ {{x=11+2*(-6)} \atop {y=-6}} \right.

\left \{ {{x=11-12} \atop {y=-6}} \right.

\left \{ {{x=-1} \atop {y=-6}} \right.

c) \left \{ {{y+3x=0} \atop {2x-y=15}} \right.

\left \{ {{y=-3x} \atop {2x-(-3x)=15}} \right.

\left \{ {{y=-3x} \atop {2x+3x=15}} \right.

\left \{ {{y=-3x} \atop {5x=15}} \right.

\left \{ {{y=-3x} \atop {x=\frac{15}{5} }} \right.

\left \{ {{y=-3x} \atop {x=3}} \right.

\left \{ {{y=-3*3} \atop {x=3\right.

\left \{ {{y=-9} \atop {x=3}} \right.

d)\left \{ {{x-y=1} \atop {x+y=17}} \right.

\left \{ {{x=1+y} \atop {1+y+y=17}} \right.

\left \{ {{x=1+y} \atop {2y=17-1}} \right.

\left \{ {{x=1+y} \atop {2y=16}} \right.

\left \{ {{x=1+y} \atop {y=\frac{16}{2} }} \right.

\left \{ {{x=1+y} \atop {y=8}} \right.

\left \{ {{x=1+8} \atop {y=8}} \right.

\left \{ {{x=9} \atop {y=8}} \right.

e) \left \{ {{4x+2y-8=5x-2} \atop {32x-y+6=24x+12}} \right.

\left \{ {{4x+2y-5x=-2+8} \atop {32x-y-24x=12-6}\right.

\left \{ {{2y-x=6} \atop {8x-y=6}} \right.

\left \{ {{x=2y-6} \atop {8(2y-6)-y=6}} \right.

\left \{ {{x=2y-6} \atop {16y-48-y=6}} \right.

\left \{ {{x=2y-6} \atop {15y=6+48}} \right.

\left \{ {{x=2y-6} \atop {15y=54}} \right.

\left \{ {{x=2y-6} \atop {y=\frac{54}{15} }} \right.

<img src="https://tex.z-dn.net/?f=%5Cleft%20%5C%7B%20%7B%7Bx%3D2y-6%7D%20%5Catop%20%7By%3D%5Cfrac%7

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