Geometry Similarity

First, a "similarity statement" is something like [MATH]\Delta XYZ\sim\Delta PQR[/MATH], where the angles at X and P are the same, and so on -- that is, the corresponding vertices are listed in the same order.

Can you identify the appropriate order in which to write the vertices A, B, and C to match DEF?

Then you'll want to look in your textbook for an example where they write proportions of side lengths, and try doing that with your two triangles. Write back showing what you've done on these two tasks, and we can continue from there.
 
Dr.Peterson said:
First, a "similarity statement" is something like [MATH]\Delta XYZ\sim\Delta PQR[/MATH], where the angles at X and P are the same, and so on -- that is, the corresponding vertices are listed in the same order.

Can you identify the appropriate order in which to write the vertices A, B, and C to match DEF?

Then you'll want to look in your textbook for an example where they write proportions of side lengths, and try doing that with your two triangles. Write back showing what you've done on these two tasks, and we can continue from there.
Click to expand...
DEF ~ ABC
 
Good; that narrows down the choices, doesn't it?

Now see what you can do writing a proportion among the sides. In general, the ratio of any side of the first triangle to the corresponding side of the second will all be the same.
 
Dr.Peterson said:
Good; that narrows down the choices, doesn't it?

Now see what you can do writing a proportion among the sides. In general, the ratio of any side of the first triangle to the corresponding side of the second will all be the same.
Click to expand...
Can you please explain this part to me?
 
I believe I saw you do it in another thread, at least for a simpler case. Please give it a try, so I can tell you how close you are.

What you write will look like

(...)/(...) = (...)/(...) = (...)/(...)​

with a number or expression in each spot. Then you'll be picking some pairs to solve; but I'm not asking you to do that yet.
 
Dr.Peterson said:
I believe I saw you do it in another thread, at least for a simpler case. Please give it a try, so I can tell you how close you are.

What you write will look like

(...)/(...) = (...)/(...) = (...)/(...)​

with a number or expression in each spot. Then you'll be picking some pairs to solve; but I'm not asking you to do that yet.
Click to expand...
I can’t do it with these numbers.
 
If you don't try things, you won't learn. You must not let yourself depend on other people, by waiting for them to show you what to do.

Often, when you try something based on what little you do understand, and then check whether it makes sense, you discover that you actually can understand what you are being taught. That can be liberating!

So, please, write down something so we can at least tell you whether you got part of it right.
 
Dr.Peterson said:
If you don't try things, you won't learn. You must not let yourself depend on other people, by waiting for them to show you what to do.

Often, when you try something based on what little you do understand, and then check whether it makes sense, you discover that you actually can understand what you are being taught. That can be liberating!

So, please, write down something so we can at least tell you whether you got part of it right.
Click to expand...
Okay I completely understand thank you, this is a little more complex to my understanding even with my notes. So for this would I have to find the ratio of the sides or solve for x first?
 
rachelmaddie said:
Okay I completely understand thank you, this is a little more complex to my understanding even with my notes. So for this would I have to find the ratio of the sides or solve for x first?
Click to expand...
I never worked with finding the ratio with numbers like this, my teacher did not show me this.
 
Start by listing corresponding sides:

AB= , DE =
BC = , EF =
CA = , FD =

Then the ratios you want are [MATH]\frac{AB}{DE} = \frac{BC}{EF} = \frac{CA}{FD}[/MATH].

Fill that in, and you will have done what I've asked so far.
 
Dr.Peterson said:
Start by listing corresponding sides:

AB= , DE =
BC = , EF =
CA = , FD =

Then the ratios you want are [MATH]\frac{AB}{DE} = \frac{BC}{EF} = \frac{CA}{FD}[/MATH].

Fill that in, and you will have done what I've asked so far.
Click to expand...
AB = 2x , DE = 2
BC = 3x - 0.6 , EF = 2.6
CA = 3.6 , FD = 2.4
 
So ... can you write three ratios that have to be equal? Can you turn a pair into an equation to solve?

I don't enjoy pulling teeth ...
 
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