Respuesta :

Answer:

The solution to the system of the equations be:

  • (x, y) = (-3, -5)

Step-by-step explanation:

Given the system of equations

[tex]2x - 3y = 9[/tex]

[tex]-5x - 3y = 30[/tex]

Solving the system of equations using the elimination method

Multiply [tex]2x-3y=9[/tex] by 5:  [tex]10x-15y=45[/tex]

Multiply [tex]-5x-3y=30[/tex] by 2:  [tex]-10x-6y=60[/tex]

[tex]\begin{bmatrix}10x-15y=45\\ -10x-6y=60\end{bmatrix}[/tex]

adding the equations

[tex]-10x-6y=60[/tex]

[tex]+[/tex]

[tex]\underline{10x-15y=45}[/tex]

[tex]-21y=105[/tex]

now solving -21y = 105 for y

[tex]-21y=105[/tex]

Divide both sides by -21

[tex]\frac{-21y}{-21}=\frac{105}{-21}[/tex]

Simplify

[tex]y=-5[/tex]

For 10x - 15y = 45 plug in y = -5

[tex]10x-15\left(-5\right)=45[/tex]

Apply the rule -a(-a) = a

[tex]10x+15\cdot \:5=45[/tex]

[tex]10x+75=45[/tex]

Subtract 75 from both sides

[tex]10x+75-75=45-75[/tex]

Simplify

[tex]10x=-30[/tex]

Divide both sides by 10

[tex]\frac{10x}{10}=\frac{-30}{10}[/tex]

Simplify

[tex]x=-3[/tex]

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

  • (x, y) = (-3, -5)

The graph of the solution to the system of equations is also attached below.

Ver imagen asifjavedofficial

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