It would be: 5/2930 = 0.0017
To find the area of a circle, you do π × diameter (in this case 10). They have told you to use 3.142 as π, so you do 3.142 × 10 = 31.42. Because it's a semi-circle, you need to halve 31.42 to get 16.21, which is the answer
Answer:

Step-by-step explanation:
Given

Required
Find x
We have:

Rewrite as:

Expand

Factorize

Factor out x + 520

Split

Solve

Side length must be positive;
So:

-10 and -1 multiply to get 10 and add to get -11