substitution problem

[Diana Veloz]

I need help with the subsitutionsproblems cause it's says to use the substitution method and i dont know what is the substitution method could you help me in ths problem

y=x+3
3x-y=5

 

[Unco]

y = x + 3 so we can replace y with x+3 in the second equation:

3x - y = 5 becomes 3x - (x + 3) = 5

You can now solve for x, and then use either equation to find y.