Question

Solve the system of equations

4x+3y=16
y=x+3
X=
Y=

Answer 1

x = 1 and y = 4

Explanation:

Because y = x + 3 we can substitute 3y with 3(x + 3)

4x + 3(x + 3) = 16

4x + 3x + 9 = 16

7x + 9 = 16

7x + 9 - 9 = 16 - 9

7x = 16 - 9

7x = 7

7x ÷ 7 = 7 ÷ 7

x = 7 ÷ 7

x = 1

Since y = x + 3 and x = 1 y = 4.

1 + 3 = 4

x = 1 and y = 4

Check:

x = 1 and y = 4

1 x 4 + 3 x 4 = 16

4 + 12 = 16

Answer 2

First you substitute.

`4x+3(x+3)=16\\4x+3x+9=16\\7x=7\\x=1\\y=4`