7x+8y=10 5x+y=−7 solve by elimination

(-2,3)

Step-by-step explanation:

7x+8y=10

5x+y=-7

To solve this by elimination, we need both equations in the same form.  There are.  They are both in form ax+by=c.

Now we also need for one of the columns with the variables to be opposite or same terms.

I like the way the column with the y's are looking because if I multiply that second y by 8 or -8 I will have sames or opposites.

I'm going to multiply the second equation by -8.

This will give me:

  7x+8y=10

-40x-8y=56

Add the equations!

-33x+0=66

 -33x   =66

      x    =66/-33

       x  =-2

Now we need to find the other variable. It doesn't matter which equation you use.

I'm going to use 5x+y=-7 where x=-2 to find y.

5(-2)+y=-7

-10+y=-7

Add 10 on both sides

     y=3

The solution is (-2,3)

d

step-by-step explanation:

6 meters

step-by-step explanation: