SOLUTION: Please help me with substitution method !! 3(2x+y)=4x+20 x-2y=3

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Question 443936: Please help me with substitution method !!
3(2x+y)=4x+20
x-2y=3
Answer by chriswen(106) About Me  (Show Source):
You can put this solution on YOUR website!
3(2x+y)=4x+20 ...(i)
x-2y=3 ...(ii)
x=3+2y ...(iii)
...
Substitute x=3+2y(iii) into (i)
...
3[2(3+2y)+y]=4(3+2y)+20 ... (iv)
3(6+4y+y)=12+8y+20
3(6+5y)=32+8y
18+15y=32+8y
15y-8y=32-18
7y=14
y=14/7
y=2 ...(v)
...
substitute y=2(v) into (iii)
...
x=3+2(2) ...(vi)
x=3+4
x=7
...
Therefore, x=7 and y=2.