Question

I don't understand them

Answer 1

7: Answer: $(x,y)=(\frac{5}{4},\frac{3}{2} )$

Substitute the value of Y:

$-2x-3(10x-11)=-7$

Solve for X:

$-2x-3(10x-11)=-7$

$x=\frac{5}{4}$

Substitute the value of X:

$x=\frac{5}{4}$

$y=10*\frac{5}{4}-11$

Solve for Y:

$y=10*\frac{5}{4}-11$

$y=\frac{3}{2}$

Solution:

$(x,y)=(\frac{5}{4},\frac{3}{2} )$

8: Answer: $(x,y)=(3,-2)$

Substitute the value of Y:

$4x-3*(-2)=18$

Solve for X:

$4x-3*(-2)=18$

$x=3$

Solution:

$(x,y)=(3,-2)$

9: Answer $(x,y)=(0,-2)$

Substitute the value of Y:

$-3x+6(-2+5x)=-12$

Solve for X:

$-3x+6(-2+5x)=-12$

$x=0$

Substitute the value of X:

$x=0$

$y=-2+5*0$

Solve for Y:

$y=-2+5*0$

$y=-2$

Solution:

$(x,y)=(0,-2)$

10: Answer $(x,y)=(-3,-6)$

Substitute the value of Y:

$-5x-(6+4x)=21$

Solve for X:

$-5x-(6+4x)=21$

$x=-3$

Substitute the value of X:

$x=-3$

$y=6+4x(-3)$

Solve for Y:

$y=6+4x(-3)$

$y=-6$

Solution:

$(x,y)=(-3,-6)$

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