Solve the system of linear equations by substitution.

{
y
=

3
x
+
1

7
x

3
y
=

9

1 answer

First, we can use the first equation to solve for y in terms of x.

y = -3x + 1

Next, we substitute this expression for y into the second equation and solve for x:

-7x - 3(-3x + 1) = -9
-7x + 9x - 3 = -9
2x - 3 = -9
2x = -6
x = -3

Now that we have found x, we can substitute it back into the first equation to solve for y:

y = -3(-3) + 1
y = 9 + 1
y = 10

Therefore, the solution to the system of equations is x = -3 and y = 10.