SOLUTION: i dont know how to do substitution algebra tiles! I'm extremely confused on HOW to solve substitutions. Please help me I'm having a hard time! 1. y= 2X 3X+y= 10

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Question 119635: i dont know how to do substitution algebra tiles! I'm extremely confused on HOW to solve substitutions. Please help me I'm having a hard time!


1. y= 2X

3X+y= 10
I'd REALLY appreciate the help!
Answer by scott8148(6628) About Me  (Show Source):
You can put this solution on YOUR website!
when you use substitution, you SUBSTITUTE the value of one unknown in terms of another unknown

the first equation tells you that y and 2X are the same (equal)

when you go to the second equation, you SUBSTITUTE 2X in place of y __ 3X+(2X)=10

so 5X=10, and X=2

now, you can go to any equation that has X and y
___ and SUBSTITUTE 2 for X to find y

y=2X __ y=2(2) __ y=4