Answer:
<h2> y = 0.25x + 2</h2>Step-by-step explanation:
(0, 2) ⇒ x₁ = 0, y₁ = 2
(-4, 1) ⇒ x₂ = -4, y₂ = 1
So the slope:
The point-slope form of the equation of the line passing through point (x₀,y₀) and with slope m is: y - y₀ = m(x - x₀)
m = 0.25
(0, 2) ⇒ x₀ = 0, y₀ = 2
Therefore:
y - 2 = 0.25(x - 0)
y - 2 = 0.25x {add 2 to both sides}
y = 0.5x + 2 ← the slope-intercept form of the equation
Answer: 119,616
You may have to erase the comma when inputting the answer.
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Explanation:
The author sells 21,000 books in the first month.
Then they sell 21,000*(1-0.12) = 21,000*(0.88) = 18,480 in the second month.
Then they sell 18,480*(1-0.12) = 18,480*(0.88) = 16,262.4 = 16,262 in the third month.
And so on. These values follow a geometric sequence with first term a = 21,000 and common ratio r = 0.88
We can think of the 0.88 as 88% of the original value (since losing 12%, we keep the remaining 88%)
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Use the formula below to sum the first 9 terms of the geometric sequence
Plug in a = 21000 and r = 0.88
The author sold about 119,616 books over the course of the first nine months.