So you have to find 15 percent of 900 which would be 135
157 degrees ... set 4x-5 = x+16 then solve, you should get x=7, plug in 7 for one of the equations and you'll get 23. subtract 23 from 180 and get 157. hope that helped :)
Answer:
SSS
Step-by-step explanation:
All sides with the same amount of lines are congruent
We’re going to use the formula for area of a rectangle, which is length x width. We are also going to use the formula for area of a triangle which is 1/2 x base x height.
Let’s start with the rectangle under the triangle ends of the roof. They are 11mm wide, 10mm high, and there are two of them.
11 x 10 x 2 = 220
Then the other sides that are 16 x 10. There are 2 of them.
16 x 10 x 2 = 320
Then the rectangular pieces of roof, 9.7 x 16, and there are 2 of them.
9.7 x 16 x 2 = 310.4
Lastly, the triangle pieces of roof. (1/2)(base)(height), but there are 2 of them
1/2 x 11 x 8 x 2 = 88
Add up all the parts:
220 + 320 + 310.4 + 88 = 938.4 mm
Use the formula that states that the sum of the angles of an n-sided polygon is given by
S=(n−2)180
0
........(1)
Since we are given that the two angles are right angles and each of the remaining angles is 144
0
, therefore, the sum is:
S=90
0
+90
0
+(n−2)144
0
.........(2)
Therefore setting (2) equal to (1) we get
(n−2)180
0
=90
0
+90
0
+(n−2)144
0
⇒(n−2)180
0
−(n−2)144
0
=180
0
⇒(n−2)(180
0
−144
0
)=180
0
⇒(n−2)(36
0
)=180
0
⇒n−2=
36
180
⇒n−2=5
⇒n=5+2=7
Hence, the polygon has 7 sides.
