If I am attempting to find the perimeter of a triangle in which the side lengths given are 7x centimeters and 5x + 16 centimeters what is the last side length
No it does not.
Ok then. I got the answer.
In an equilateral triangle, all the side lengths are the same.
So that means 7x = 5x + 16.
Subtract 5x to both sides to get 2x = 16.
Divide both sides by 2 to get x = 8.
But that's not our answer. We need to plug in 8 instead of x to one of the 'sides equations.'
Let's plug it into 7x.
7(8) = 56. Remeber, we substituted 8 for x.
So we know a side of the equilateral triangle is 56 cm.
And we know that all the side lengths are the same.
So the last side length would be 56 cm.