Question

Find x and y.

20x + 25y = $650

x + y = 30

Answer 1

x = 20

y = 10

Explanation:

Rewrite the 2nd equation to make x the subject:

x + y = 30 ⇒ x = 30 - y

Substitute x = 30 - y into the first equation and solve for y:

20(30 - y) + 25y = 650

600 - 20y + 25y = 650

600 + 5y = 650

5y = 50

y = 10

Substitute found value of y into x = 30 - y to find x:

x = 30 - 10 = 20

So x = 20 and y = 10