Answer:

Step-by-step explanation:
First, calculate the area of the rectangle.
Here, length = 18 units and Width = 12 units
The formula for calculating the area of the rectangle is 

The radius of the semi-circle is 6 units.
The formula for calculating the area of the semi-circle is
.

The area of the shaded region is equal to the difference of area of the rectangle and area of the semi-circle.

Answer:
17
Step-by-step explanation:
These two angles add up to 180, so we can set up an equation. 5x-23+7x-1=180. Now we combine like variables, getting 12x-23-1=180. We add 23 to both sides, and get 12x-1=203. Then we add 1 to both sides, getting 12x=204. Finally we divide by 12 on both sides, with our result as x=17.
X=12 is the answer, i have done this question before, hope i helped.
Answer:
7.863
Step-by-step explanation: