If y-3=7 and x+3y=6 then x=?

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I can't answer x+3y=6 right now. I have two variables (x and Y) so I'm stuck.

So, I turn to my other equation. y-3=7. If I add three to each side of the equation, I get y=10.

Now that I know y=10, I can put the number 10 in every place there was a "y." So, the second equation looks like this...

x+3y=6

x+3(10)=6

x+30=6 So I subtract 30 from each side.

x=-24

I then check myself by putting all my numbers back into the original equations.

10-3=7 and -24+3(10)=6

Yep, that works.

Well

x+3y=6 and y-3=7

(+3)y-3=7(+3)

y=10

x+3(10)=6

x+30=6

x= -24

y-3=7

y-3+3=7+3

y=10

x+3y=6

x+3(10)=6

x+30=6

x+30-30=6-30

x=-24

If y-3=7 and x+3y=6 then x=?

First solve for y because we have enough information for that.

y = 3 + 7 = 10

plug into the other equation:

x + 3(10) = 6

x + 30 = 6

x = 6 - 30 = -24

y-3=7 and x+3y=6 then x=

y - 3 = 7

+3 +3

y=10

plug in the number in the second problem

x+3(10)=6

x+30=6

-30 -30

x= -24

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