I am given two triangles

One triangle has side length of 4 and 2x+7
The other one has side length of x and 1.

How do I find the lengths of the sides of these two similiar triangles

2 answers

I know I use proportions but Im stuck
if the two sides given are corresponding sides, then they have a common ratio:

x/4 = 1/(2x+7)
x(2x+7) = 4
2x^2+7x-4=0
(2x-1)(x+4) = 0
x = 1/2

so the triangles have sides of

4,8 and 1/2,1