Solve:
[tex]x = - 2y - 3 \\ 4y - x = 9[/tex]
Step1:
Get the variable (x or y) alone or find the equation that has the variable already alone, which would be the first equation.
[tex]x = - 2y - 3[/tex]
Step 2:
Replaced "x" in the second equation with the equation in the first equation. This is used to find "y"
[tex]4y - ( - 2y - 3) = 9[/tex]
Step 3:
Solve and Simplify
[tex]4y + 2y + 3 = 9[/tex]
[tex]6y + 3 = 9[/tex]
[tex]6y + 3 - 3 = 9 - 3[/tex]
[tex]6y = 6[/tex]
[tex] \frac{6y}{6} = \frac{6}{6} [/tex]
[tex]y = 1[/tex]
Step 4:
Use one of the original equation:
[tex]x = - 2y - 3 \\ 4y - x = 9[/tex]
Replace "y" from any of the problem (I recommended the first equation) to find "x"
[tex]x = - 2(1) - 3[/tex]
[tex]x = - 2 - 3[/tex]
[tex]x = - 5[/tex]
The answer is: (-5, 1)
To check your answer:
[tex]x = - 2y - 3[/tex]
[tex] (- 5)= - 2(1) - 3[/tex]
[tex]( - 5) = - 2 - 3[/tex]
[tex]( - 5) = - 5[/tex]
You will find the same answer if u use the other way. But, the way I show you is much easier and faster to find the answer.
I hope this helped u
