7x-6y=-1 5x-4y=1solving for eliminatio

Sagot :

multiply the first equation by 5 and 2nd by -7 and you get 

35x-30y=-5 
-35x+28y=-7 

now you can cancel out the x's and you get 

-2y=-12 

so 

y=6 

now you can just plug y=6 into one of the original equations and you will see that x turns out to be 5

Hope thats okay
[tex]7x-6y=-1 \ \ \ |\times (-2) \\ 5x-4y=1 \ \ \ |\times 3 \\ \\ -14x+12y=2 \\ \underline{15x-12y=3 \ \ \ } \\ 15x-14x=2+3 \\ x=5 \\ \\ 5x-4y=1 \\ 5 \times 5-4y=1 \\ 25-4y=1 \\ -4y=1-25 \\ -4y=-24 \\ y=\frac{-24}{-4} \\ y=6 \\ \\ \boxed{(x,y)=(5,6)}[/tex]