Question

How to solve for x I don’t know how to.

Answer 1

We are given the triangles:

We know:

AB = 20

BC = 12

DB = 2x + 7

BE = 9

EC = 3

The triangles ABC and DBE are similar, which means, that there is a number k, such that each side of the triangle ABC multiplied by k is equal to the corresponding side in triangle DBE

We can find the number k, using the sides BC and BE:

`k\cdot BC=BE`

Substitute and solve:

`\begin{gathered} k\cdot12=9 \\ . \\ k=(9)/(12) \\ . \\ k=(3)/(4) \end{gathered}`

Now, we can find x because:

`(3)/(4)AB=DB`

Substitute and solve:

`\begin{gathered} (3)/(4)\cdot20=2x+7 \\ . \\ 15-7=2x \\ x=(8)/(2) \\ . \\ x=4 \end{gathered}`

The answer is x = 4