Question 308810
Hello, 
Let's have x represent the shortest side. The other side will be x+7 and the other is shown by 2x+3. Now we can set up the equation as:
x+(x+7)+(2x+3)=30 Combine like terms and subtract 10 from both sides to get:
4x=20 Divide both sides by 4 to get:
x=5 
So the short side is 5 cm. I'll let you figure out the other sides now. 
Make sense?
RJ
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