# How do you solve #35x - 5y = 20# and #y = 7x + 4# using substitution?

##### 2 Answers

See a solution process below:

#### Explanation:

**Step 1)** Because the second equation is already solved for

This indicates there are no solutions to this system of equations. Or, no solution set is the empty or null set:

This also indicates, if there is no solutions, that these equations represent parallel lines.

"Substitute" the expression for y in the second equation into the first one.

#### Explanation:

0 does not = 40, so there is no solution to this set.

Converting both to slope-intercept form gives us:

They are parallel lines (same slope) with different intercepts (4 and -4).