What is the value of y in the following system? 5x + y = 9

10x - 7y = - 18

y = 4

Step-by-step explanation:

given the 2 equations

5x + y = 9 → (1)

10x - 7y = - 18 → (2)

Multiplying (1) by - 2 and adding to (2) will eliminate the term in x

- 10x - 2y = - 18 → (3)

Add (2) and (3) term by term on both sides

(10x - 10x) + (-7y - 2y) = ( - 18 - 18)

0 - 9y = - 36

- 9y = - 36 (divide both sides by - 9)

y = 4

y = 4

Step-by-step explanation:

We have given a system of equation.

5x+y = 9 eq (1)

10x-7y = - 18 eq (2)

We have to find the value of y.

Multiplying eq (1) by 2, we have

10x+2y = 18

Subtracting above equation from eq (2), we have

10x+2y - (10x-7y) = 18 - (-18)

10x+2y-10x+7y = 18+18

9y = 36

y = 4 which is the answer.