Answer:
D. 73°
Step-by-step explanation:
The inside angles of a triangle always equal 180° so if we know that a right angle is already 90° we only need one more angle to know all of them:
1. 90° + 17° + ?° = 180
2. 90° + 17° = 107°
3. 180° - 107° = 73°
4. 90° + 17° + 73° = 180
5. XD
35
Area of rectangle
21m^2
Area of one triangle
divide length of 7 by 2 (3.5)
gives you length b (unknown side that is not hypotenuse)
then multiply by width of triangle (4)
3.5 * 4 = 14
and in this situation there is no need to divide by two, because you essentially have one full square from both the triangles. this only works when both triangles are the same.
add the area of the rectangle
14+21= 35
35m^2
So we know that the swimming pool is 15 by 7 meters wide.
15 times 7 is 105.
Now, a tile costs $6 and covers 1 square meter.
So, we should multiply 105 by 6, which would give us 630.
So, if I'm correct, the answer should be that it costs him $630 to install the tiles on the swimming pool.
(sorry if I'm incorrect)