Question

hey

Answer 1

5. In the two similar trapezoids below, HE = 20, what is DA?

Answer 2

wanna help?

Answer 3

Hint: If two geometric figures are SIMILAR, every side of one is proportional to the corresponding side in the other.

Or, in other words, you can set up ratios and set the ratios equal to one another.

Here's an example: The ratio of side EF to side AB is equal to the length of EF over 70.\[\frac{ Length.of.EF }{ Length.of.AB }=\frac{ Length.of.EF }{ 70 }\]

Answer 4

Have you seen this before? If so, do y ou know what the next step is?

Answer 5

Can you explain, in your own words, what our goal is in this problem?

Answer 6

um the goal is to find out whats DA?

Answer 7

im seriously terrible at math

Answer 8

But not for long! Persistence and patience will get you a long way towards understanding math.

Right. So, you know that the length of side HE is 20 and that you have to find the length of side DA.

As before, write a ratio: HE/20

We'll hold this for a moment.

We need to find some intermediate info first. What I'd like to do is to determine the length of side CD. I'll explain why in a moment.

Answer 9

would you agree that the side of length 56 in the smaller figure corresponds to the side of length 42x in the larger?

Answer 10

and that the side of length 10x in the smaller figure corresponds to the side of length 30 in the larger?

Answer 11

Before we move on, are you comfortable with the phrase "corresponds to" as used here in geometry?

Answer 12

@armine, you can do this problem, and I will help you through it if you wish. If you're busy with something else, we could pick this work up later. But I'd like to know your intentions.

Answer 13

If you decide to get involved in this problem solving again, answer whichever of my questions you can. I will read what you have written next time I'm on OpenStudy, and will then respond.

Answer 14

well wat i did to get the answer was i saw how long HE was then see how many HE will fit in DA .

Answer 15

@armine : I have done this problem in two different ways. Once you've seen what to do, the problem's not so hard. But it will require several different steps. Only you can decide whether or not you have the patience and interest necessary to arrive at a solution.