Answer
Infinitely many solutions
Work Step by Step
Simplify 21x - 35 = 7y
$\frac{21x - 35}{7}$ = $\frac{7y}{7}$
3x - 5 = y
This is equal to the other equation, 3x - 5 = y
Any solution on 3x - 5 = y would satisfy 21x - 35 = 7y, and vice versa
Therefore the system has infinitely many solutions