SOLUTION: 3x(x+3)=2(5x+1)

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Question 192498: 3x(x+3)=2(5x+1)
Answer by jojo14344(1513) About Me  (Show Source):
You can put this solution on YOUR website!


Given: 3x(x+3)=2(5x+1)
Expand:
3x%5E2%2B9x=10x%2B2
3x%5E2%2B9x-10x-2=0
3x%5E2-x-2=0, wheresystem%28a=3%2Cb=%28-1%29%2Cc=%28-2%29%29

Then,

x=%281%2B-sqrt%281%2B24%29%29%2F6=%281%2B-sqrt%2825%29%29%2F6=%281%2B-5%29%2F6

Two values:
x=%281%2B5%29%2F6=6%2F6=red%281%29
x=%281-5%29%2F6=-4%2F6=red%28-2%2F3%29

Let us check: x = 1
3x%28x%2B3%29=2%285x%2B1%29
3%281%29%281%2B3%29=2%285%2A1%2B1%29
3%2A4=2%2A6
12=12, good

x = -2/3
3%28-2%2F3%29%28-2%2F3%2B3%29=2%285%28-2%2F3%29%2B1%29
%28-2%29%28%28-2%2B9%29%2F3%29=2%28-10%2F3%2B1%29
%28-2%29%287%2F3%29=2%28%28-10%2B3%29%29%2F3
-14%2F3=2%28-7%2F3%29
-14%2F3=-14%2F3, good

Let us see the graph:


Thank you,
Jojo