1. Angle ADE and AED equals 64 degrees. Angle x is 124 degrees
2. AD and DB= 4 square root 3 . AB = 8 Square root of 3 Angle ACD and BCD - 20 dgrees
3. no idea
4. BC equals 18.3923048
5. AB - 50 square root of 2
7. I have no idea how to do this please help me
8. AC= 20 BC=10 square root of 3
9. Area is 24 AC=8
10. I have no idea please help me
Sep 26th 2009, 06:58 PM
1. x is correct, but you divided incorrectly, so ade and aed are each 62, not 64.
2. Why would ACD and BCD equal 20? Because ACB is equilateral, each of the angles should be 1/3 of 180, which is 60 per angle. DC will bisect the angle so ACD and BCD should each be 30
3. First, AC=13. BCD~ABC, with a ratio of 13:5 Therefore BD~AB with the same ratio of 13:5. So BD=AB*5/13=12*5/13=4.61538. I believe that's right, but check to see if it makes sense to you.
7. Because ad=db and ae=ec, the two triangles must be similar with a ratio of 1:2 So area=1/2bh and h_abc and b_abc are 2 times as large as the h_ade and b_ade respectively. Therefore A_abc=1/2(2b_ade)(2h_ade)=4*A_ade. So A_abc=64. But you need to find A_bcde=A_abc-A_ade=64-16=48.
10. After having seen how to do 7 do you still believe that you don't know how to do this question? Try it yourself first and post the answer to see if you were correct.