10. from the question; the circle theorem obeyed is "angled formed by semi-circle"
The angle formed in a semicircle is 90 degrees, hence

This gives

But

Substituting values we get

hence, x =12
Answer:
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Step-by-step explanation:
Given
In 1990; Income= $39000
In 2010; Income= $70768
Solving (a): An equation in form of f(x) = ax + b
First, we need to determine the slope, a

Taking y as income and x as year index.
When x = 0; y = 39000
When x = 20; y = 70768
Substitute these values in the above formula



Next, is to determine the formula using:

<em>Considering :When x = 0; y = 39000, we have</em>
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<em>Make y the subject of formula</em>
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<em>Express y as a function of x</em>
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Solving (b): Income in 2005
<em>In 2005, x = 15</em>
So:
becomes


a is the beggining number and n is the amount of times needed to do this. if is 17 you would need to subtract 7 from the originol number 12 (a) that many times.
X^2 - 3x + 5
2^2 - 3(2) + 5
4 - 6 + 5
3
I think question statement c is false about proof