Asystem of equations is shown. 4x + 20 = 5y x + 15 = 3y what is the solution for the given system of equations?

I would first rearrange the second equation to get x by itself

x+15=3y
x=3y-15

Then I would substitute 3y-15 in for x in the first equation. I would do this because x has the same value as 3y-15

4(3y-15)+20=5y
12y-60+20=5y
12y-40=5y
-40=-7y
5.7=y

Then plug y back into an equation to get x

x+15=3(5.7)
x+15=17.1
x=2.1

Hope this is correct :)

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