Help in geometry finding area please

http://tinypic.com/view.php?pic=i5dx4x&s=7

what is the formula to find area of 1 -4

how would i find the missing angle of 5

and how would i find 6 & 7 totally confused please help.

1-4 - divide the figures into standard geometric figures like rectangle , circle , semi-circle , triangle etc and then calculate individual area , then sum up areas of all figures.

1. there is one rectangle and two semi-circles , so Area = (length * breadth) +pi*(21/2)^2

2. one rectangle , one triangle and one semi-circle.

3. one semi-circle two triangles.

4. I couldn't solve this , but you may try it at your own, they are pretty much like 1 to 3.

5. y = 101 (vertically opposite angles) , x=180-y as x and y are linear pair so they are forming 180 degree angle

6. sin x = perpendicular / hypotenuse

let x be angle formed by inclination and ground , h1 be height of building, h2 be height of person and A1 = 169 and A2 =13 be hypotenuse of the triangle formed.

now, sin x = h1/A1 and also, sin x = h2/A2
h1/A1=h2/A2 so h1 = h2 * (A1/A2)
h1 = 5* 169/13 = 65 ft

7. use side - side - side assumption of Euclid geometry.
if two triangles are similar then ratio of their corresponding sides are equal.

in your case, L/15=80/5
L = 240 m

1. You see two half parts of a circle? We can use a formula to for full circle to find the area of those two parts.
It's piR^2.
R= 21/2=10.5
A(circle)= (10.5)^2 pi = 110,25
Now we are left with the rectangular part. You just need to multiply width by height.
A(rectangular)=21*42=882
Now just add those areas together to get an area of figure.
A(wtf?)=882 + 110.25 = 992.25

2. Use the circle formula to find the area of half circle. Now you just need to divide the answer you'll get by 2 because you only have 1 half of circle not two like the last time.