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


No because 3 x 4 = 12 and 8 x 4 ≠ 24
to get the numbers in step 3
multiply -1.6 by 3
then multiply -1.6 by 0.1
and add them together
answer is D) (–1.6)(3) + (–1.6)(0.1)
So firstly, I'm going to be converting the mixed number into an improper fraction. To do this, multiply the whole number by the denominator and then add that product with the numerator and that will be your new numerator. In this case:
3 × 8 = 24, 24 + 3 = 27. 
Now since they have the same denominator, you can subtract the numerators.

Now simplify the number as such:

<u>In short, your answer is -17/4, or -4 1/4.</u>