Mathematics: Please do elimination method 2x-9y=-36 -14x+18y=-18

139080Step-by-step explanation:...

Please do elimination method 2x-9y=-36 -14x+18y=-18

Need1ng

16.03.2022

The solution to the system of equations will be:

$x=9,\:y=6$

Step-by-step explanation:

Given the system of equations

$\begin{bmatrix}2x-9y=-36\\ -14x+18y=-18\end{bmatrix}$

Multiply 2x-9y=-36 by 7

14x-63y=-252

so the system of equations becomes

$\begin{bmatrix}14x-63y=-252\\ -14x+18y=-18\end{bmatrix}$

Adding both equations

-14x+18y=-18

$\underline{14x-63y=-252}$

-45y=-270

solve -45y = -270 for y

-45y=-270

divide both sides by -45

$\frac{-45y}{-45}=\frac{-270}{-45}$

Simplify

y=6

For 14x-63y = -270 plug in y = 6

$14x-63\cdot \:6=-252$

14x-378=-252

Add 378 to both sides

14x-378+378=-252+378

Simplify

14x=126

Divide both sides by 14

$\frac{14x}{14}=\frac{126}{14}$

Simplify

x=9

Therefore, the solution to the system of equations will be:

$x=9,\:y=6$

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