Side Length Quotients in Similar Triangles

These 2 triangles are similar. What are $$a$$ and $$b$$ ? Note: the 2 figures are not drawn to scale.

What are the side lengths of triangle XYZ if it is similar to triangle ABC with side lengths 4, 5, and 7, and a scale factor of 1/4?

For triangle $$XYZ$$ , calculate (long side) $$\div$$ (medium side), and compare to triangle $$ABC$$ . Triangle $$XYZ$$ is similar to $$ABC$$ with scale factor $$\frac 1 4$$ . What is the ratio for triangle $$XYZ$$ ?

The 2 triangles shown are similar. Find the value of $$\frac d c$$ .

Which of the following sets of side lengths could be for Triangle B so that it is similar to Triangle A, which has side lengths 3 units, 4 units, and 5 units?