Find the perimeter of an Isosceles Triangle.

Question

There are three variables, each on one side.

(x+4)

7

(4x+1)

I don't where/how to start this question, some help would be greatly appreciated!

Answer 1

Hi,

you’re given the 3 side lengths of the triangle. In an isosceles triangle, two sides have equal lengths.

1. I don’t see a picture but I’m assuming that The two sides I’m given in terms of x should be the congruent sides. Then use

x+4 = 4x + 1

2.if 7 and one of the other sides are equal then you would use eg.

x+4 =7, I can’t tell which two sides unless I see the figure.

So using the diagram solve for x. Once you find x, you can get the measures of each side. Then add all 3 sides to get the Perimeter.

hope this helps!

Answer 2

In an isosceles triangle 2 sides are equal. I will assume the sides measuring x+4 and 4x+1 are the equal sides so we can equate:

x+4 = 4x + 1

and solve for x

x = 1

Plugging x = 1 back into those expressions you get that those sides are both of length 5.

So the perimeter of the triangle is 5 + 5 + 7 = 17