Given the system below, what would be the best way to start solving it using substitution?

Question

x+y=20

x=3y

Answer 1

The best way to start solving this system using substitution would be to isolate one variable in one of the equations and then substitute it into the other equation.

In this case, we can isolate x in the second equation:
x = 3y

Now we can substitute this expression for x into the first equation:
(3y) + y = 20

Now we can solve for y and then use that value to find x.