Question

The perimeter of an isosceles triangle is 15.6m. Find the lengths of its sides, if:

The base is 3m smaller than a leg.

Answer 1

The length of the sides are 6.2m.
This means that the base is 3.2m.

Answer 2

Since it is an isosceles triangle, 2 sides are congruent by the definition. The base will be 3m smaller than a side. Let’s write an equation:

15.6m (total perimeter)= 2L(two legs of equal length) + L-3 (Length of base)

So your equation: 15.6=2L+L-3

Now solve for L...

18.6= 3L

L= 6.2

Therefore, you know that the length of two of the sides is 6.2 m. Now, you just have to find the length of the base by subtracting 3m from that length.

6.2-3= 3.2

So, your final answer is: The length of both legs= 6.2 m

Base length= 3.2 m


Check your work! All three numbers should add up to 15.6

6.2+6.2+3.2=15.6

So, the answer is correct!

Hope this helped! Comment if you have questions!