SOLUTION: equation using substitution method y=2/3x-1 2x+3y=21

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Question 403159: equation using substitution method
y=2/3x-1
2x+3y=21
Found 2 solutions by algebrahouse.com, mananth:
Answer by algebrahouse.com(1659) About Me  (Show Source):
You can put this solution on YOUR website!
equation using substitution method
y = 2/3x - 1
2x + 3y = 21

2x + 3(2/3x - 1) = 21 {substituted 2/3x - 1 in for y into bottom equation}
2x + 2x - 3 = 21 {used distributive property}
4x - 3 = 21 {combined like terms}
4x = 24 {added 3 to both sides}
x = 6 {divided both sides by 4}

y = 2/3x - 1
y = 2/3(6) - 1 {substituted 6 in for x into top original equation}
y = 4 - 1 {multiplied 2/3 by 6}
y = 3 {combined like terms}

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Answer by mananth(16946) About Me  (Show Source):
You can put this solution on YOUR website!
y=2/3x-1......1
2x+3y=21......2
...
substitute the value of y in second equation
2x+3(2x/3-1)=21
LCD of the parenthesis is 3
2x%2B%28cross%283%29%29%282x-3%29%2F%28cross%283%29%29+=21
2x+2x-3=21
4x-3=21
add 3
4x=24
/4
x=6
...
plug value of x in (1)
y=2/3x-1
y=(2/3)*6 -1
y=3
m.ananth@hotmail.ca