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


The first number is 170
The second number is 171
Step-by-step explanation:
Let the first number be x^3 and the second number be x^3+1
The sum of the two is 341
X^3+x^3+1=341
2x^3+1=341
Substrate 1 from both sides
2x^3=341-1
4X + 8 9X+3 (this is the equation, nothing to explain in this step)
4x + 5 = 9x (you combine or subtract the like terms, 8 - 3 = 5)
5 = 5x (you do 9x - 4x = 5x, subtracting the like terms)
1 = X (your answer after dividing 5 from both sides)