ANSWER
Infinitely many solutions (0 = 0)
EXPLANATION
We have the two equations and we are to solve them simultaneously.
We have:
y = 5x + 2 ___(1)
10y - 50x = 20 ___(2)
Put (1) in (2):
We have that:
10(5x + 2) - 50x = 20
50x + 20 - 50x = 20
=> 50x - 50x = 20 - 20
=> 0 = 0
This kind of solution implies that there are infinitely many solutions to this equation.
