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anonymous
 5 years ago
The length of the bridge is 48 ft and the height is 15 ft. It is made of 5 congruent triangles. Are these triangle acute, right, or obtuse? How many feet of material is needed to build one side of the bridge?
anonymous
 5 years ago
The length of the bridge is 48 ft and the height is 15 ft. It is made of 5 congruent triangles. Are these triangle acute, right, or obtuse? How many feet of material is needed to build one side of the bridge?

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anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0please help me with this! it is really important

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0The triangles are acute.

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0sstarica might be showing why...

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0lol, I was about to say that they are all the same that's all

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0and was about to ask you why LOL

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0Okay QEvelyn, triangles are acute when each of their internal angles are less the 90 degrees. So the challenge here is to determine the angles. Here we go...

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0You have three triangles on the bottom, and the sum of their bases equals 48. The base of each triangle is then, 48/3 = 16

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0You're also told the height, which is 15. This is the same height you'd find from the base of the triangle to the apex. If you draw a perpendicular line from the apex (tip) to the bottom, it will bisect the base. You'll then have, in each triangle, two rightangled triangles with base = 8 height = 15 The hypotenuse is the side of the bigger triangle it came from. You need to find that. You can use Pythagoras' Theorem for that. So, \[s^2=8^2+15^2=289 \rightarrow s=17\]

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0lol myininaya, you've answered in the wrong place

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0oh nvm >_< her answer is gone

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0Since two of these triangles make up your larger one, because of symmetry, you have an isosceles triangle (putting the two rightangled ones back together again). The base is 16 and the sides are 17 each. Because the triangle is isosceles, the two angles at the base will be equal. Call them \[\alpha\]Let's call the angle at the top\[\theta\]By the law of cosines, \[16^2=17^2+17^22 \times 17^2 \cos \theta \rightarrow \cos \theta = \frac{161}{289}\]which implies\[\theta \approx 56.145^o\]Since the sum of the angles of a plane triangle equals 180 degrees, and since the triangle is isosceles, you have\[180^o=2 \alpha +56.145^o \rightarrow \alpha \approx 61.928^o\]Your three angles in each of the bottom triangles is then\[56.145^o, 61.928^o,61.928^o\]All of these angles are less than 90 degrees, so the triangle is acute.

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0Since you're given that the triangles are congruent, proving this for one proves for all.

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0and he strikes again ~ :)

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0I think the questioner has fled.

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0was afraid of all the writing lol

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0you've scared me, but when I read it, it was all clear :)

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0the HUGE reply came out of nowhere in a BLINK ._. LOL

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0Problem is, all this writing can be done away with if you could draw on this thing.

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0yeah , I know lol ^_^

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0he's prolly checking your reply now :)

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0Do you want to finish it  I want to go to bed?!

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0but it's already done?!

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0There's something about area.

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0well add up all the areas then,right?

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0A = 120x5 = 600 ft^2 done!

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0he'll need that much for that, I guess

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0How many feet of material or something...

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0Could be one of those frame bridges.

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0I figured the answer till the area of each, but not the material

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0I get 182 feet for one side.

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0Just check, I'm fried.

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0lol bye, I'll try to solve it though ^_^

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0I can't seem to figure out how he got 182 ft

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0sstarica, you'll kick yourself: it's just summing up each of the lengths.

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0HI GUYS thank you very much it went all over my head and sorry im so late to respond. the teacher will go over it in class next week and ill tell you all what she got. thank you again and i know who to come to again for math help! oh yeah and im a she :)

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0And I just became a fan of both of you so Iokisan, you are now a Hero!!!

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0Oh, so you're the one who clicked me over! Thank you!
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