Question

Bro whats, solve the following system of linear equations by elimination

5x + y = 9
10x - 7y =-18

Answer 1

x = 1

y = 4

Explanation:

5x + y = 9

10x - 7y = -18

Time the first equation by -2

-10x - 2y = -18

10x - 7y = -18

-9y = -36

y = 4

Now put 4 in for y and solve for x

5x + y = 9

5x + 4 = 9

5x = 5

x = 1

Let's check

5(1) + 4 = 9

5 + 4 = 9

9 = 9

So, x = 1 and y = 4 is the correct answer.

Answer 2

x=1,y=4

Explanation:

5x+y=9

5x=9-y

x=(9-y)/5

put it in 10x-7y=-18

10x((9-y)/5)-7y=-18

18-2y-7y=-18

-9y=-36

y=4

x=(9-4)/5=1