C. The square root of 144
Answer:
75.44 Square Inches
Step-by-step explanation:
The diagram of the problem is produced and attached.
To determine the area of the cleaned sector:
Let the radius of the larger sector be R
Let the radius of the smaller sector be r
Area of the larger sector 
Area of the smaller sector 
Area of shaded part =Area of the larger sector-Area of the smaller sector

From the diagram, R=10 Inch, r=10-7=3 Inch, 
Therefore, Area of the sector cleaned

We need to get x alone, to do that we add 1 to both sides to cancel out the -1 on the right.
-4 = x -1
+1 +1
-3=x
This means x is equal to -3. Hope this helps!
Answer:
w=15
Step-by-step explanation:
w/5=3
multiply by 5 on both sides
w=3*5
∴ w=15
Because when you subtract a negative number the signs cancel out and become and addition problems