word problem

Question

the longest side of a triangle is three inches longer than the shortest side. the medium side is two inches longer than the shortest side. if the perimeter of the triangle is 20 inches, what are the lengths of the three sides

Answer 1

The way to solve this is to set up expressions for the length of each side and add them together.  That should add up to the perimeter, which is 20 inches.

 

So let's call the length of the shortest side x.

 

Then the longest side is x + 3.

 

And the medium side is x + 2.

 

So the sum of all three sides is x + (x + 3) + (x + 2) = 3x + 5.  That gives us an equation:

 

3x + 5 = 20

 

Solve the equation:

3x = 15

x = 5.

 

The shortest side is x, so that's 5.  The longest side is x + 3 = 8.  And the medium side is x + 2 = 7.