How do you solve the system of equations 12x + y = 38 and 4x + 5y = 22?

1 Answer
Feb 6, 2017

Se the entire solution process below:

Explanation:

Step 1) Solve the first equation for y:

12x + y = 38

12x + y - color(12x) = 38 - color(12x)

12x - color(12x) + y = 38 - color(12x)

0 + y = 38 - 12x

y = 38 - 12x

Step 2) Substitute 38 - 12x for y in the second equation and solve for x:

4x + 5y = 22

4x + 5(38 - 12x) = 22

4x + 190 - 60x = 22

190 - 60x + 4x = 22

190 - 56x = 22

190 - color(red)(190) - 56x = 22 - color(red)(190)

0 - 56x = -168

-56x = -168

(-56x)/color(red)(-56) = -168/color(red)(-56)

(color(red)(cancel(color(black)(-56)))x)/cancel(color(red)(-56)) = 3

x = 3

Step 3) Substitute 3 for x in the solution to the first equation at the end of Step 1 and calculate y:

y = 38 - 12x

y = 38 - (12 xx 3)

y = 38 - 36

y = 2

The solution is x = 3 and y = 2