Question

`x+3y=23\\ x-2y=-7`

Answer 1

y = 6

x = 5

Explanation:

System of equations

Make x as the subject in both equations:

x + 3y = 23 -----> (1)

x = 23 - 3y ----> (2)

x - 2y = -7 -------> (3)

x = -7 + 2y -----> (4)

As, (2) = (4):

23 - 3y = -7 + 2y

Now let us make "y" the subject:

First, add 3y to both sides.

23 = - 7 + 2y + 3y

23 = -7 + 5y

Add 7 to both sides.

23 + 7 = 5y

30 = 5y

Divide both sides by 5.

6 = y

Now replace y with 6 in equation (2):

x = 23 - 3y

x = 23 - 3 × 6

x = 23 - 18

x = 5