find the solution to system by the substitution method.

y=2x+5
y=3x

The answer is(5,15). Just don't know how the professor got that answer.

y = 2x+5

y = 3x
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Substitute 3x for y in equation 1.
3x = 2x+5
x=5

Then put x in equation 2 for
y = 3x or 3*5 = 15