Question

Solve each system by elimination 9) 5x+y=9 10x-7y=-18

Answer 1

Answer:

x=1, y=4

Step-by-step explanation:

5x+y=9

10x-7y=-18

To solve by elimination, we pick a variable to eliminate, or get rid of.  I will multiply the first equation by -2 so we can get rid of x

-2( 5x+y)=9 *-2

-10x -2y = -18

Now we add this equation to the second equation

-10x -2y = -18

10x-7y=-18

-------------------------

-9y = -36

Divide each side by -9

-9y/-9 = -36/-9

y =4

We still need to solve for x

5x+y=9

Put in y=4

5x+4 = 9

Subtract 4 from each side

5x +4-4 = 9-4

5x = 5

Divide each side by 5

5x/5 = 5/5

x=1