In the figure, the ratio of the perimeter of rectangle ABDE to the perimeter of triangle BCD is ___ . The area of polygon ABCDE is ___ square units. part 1 options 2/3 1 3/2 2 Part 2 options 18 22 24 28 Please help me I cant figure this out to save my life and I need to finish by tomorrow or I can't go on my senior trip. I'll fan and give anyone a medal that can help me!
https://cdn.ple.platoweb.com/EdAssets/35d21e00057140ab829a717857a217fa?ts=635375425111030000 < link to figure
were you able to find the perimeter of rectangle ABDE?
32?
what is the base of the rectangle? I.e, what is the distance from D to E?
2
yep, how about the height? what is the distance from E to A?
6 so the perimeter of the rectangle is 12?
|dw:1464739528416:dw|
the rectangle ABDE looks like this
add up the four sides 2+6+2+6 = 8+8 = 16
so the perimeter of ABDE is 16 units do you agree with this statement?
yes
ok now onto the triangle
how long is segment BD?
6
yes
to find the other 2 sides, we will need to use the distance formula have you learned this formula in your lesson?
Not that I found
have you learned the pythagorean theorem?
a^2 + b^2 = c^2?
yes
so we start with this https://cdn.ple.platoweb.com/EdAssets/35d21e00057140ab829a717857a217fa?ts=635375425111030000 what I would do next is draw in red segments as you see in the attached document
based on this http://assets.openstudy.com/updates/attachments/574e2196e4b056c4b3e61ce0-jim_thompson5910-1464740094550-triangle1.jpg how long is the green segment? how long is the red segment?
4 and 3
very good
focus on that triangle and we see this |dw:1464740172111:dw|
to find the distance from D to C is the same as finding the hypotenuse x
in this case a = 4 b = 3 c = x c is always the longest side |dw:1464740228995:dw|
do you know how to use this info to find the value of c?
I honestly have no idea. would that still be 6 or no?
\[\Large a^2+b^2 = c^2\] \[\Large 4^2+3^2 = x^2\] \[\Large 16+9 = x^2\] \[\Large 25 = x^2\] \[\Large x^2 = 25\] If x^2 = 25, then x = ???
5?
yes, so the distance from D to C is 5 units this is the same as saying segment DC is 5 units long
now draw in additional segments to form another right triangle
what are the lengths of those vertical and horizontal segments?
3 and 4?
yes, so how long is BC?
5 units?
yep
to summarize triangle BCD, so far, we have BD = 6 DC = 5 BC = 5 what is the perimeter of triangle BCD?
16?
yes
the perimeter of rectangle ABDE is 16 units the perimeter of triangle BCD is 16 units
so the answer is 1?
to find `the ratio of the perimeter of rectangle ABDE to the perimeter of triangle BCD` we divide the two values ratio = (perimeter of rectangle)/(perimeter of triangle) = 16/16 = 1
yes the answer to the first part of the question is 1
so is the second part 24?
let me check
You nailed it. Nice job.
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