Answer:
P = 0.09r²
Step-by-step explanation:
Price, p is proportional to the square of its radius, r
P = k*r²
a mirror with radius 20cm has a price of £36
P = k * r²
36 = k * 20²
36 = k * 400
36 = 400k
k = 36/400
k = 0.09
Substitute the value of k into the equation:
P = k * r²
P = 0.09 * r²
P = 0.09r²
The answer is B estimated number is 20
Answer: A.) It is a linear function because there is a constant rate of change in both the input and output values.
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Explanation:
Note how x is decreasing by 3 each time
- -2-3 = -5
- -5-3 = -8
- -8-3 = -11
At the same time, y is also decreasing by 3 each time
This means we have a linear function. We have,
slope = (change in y)/(change in x)
slope = (-3)/(-3)
slope = 1
Recall that slope is another term for rate of change, so a constant slope means we have a constant rate of change.
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Another way to find the slope is to pick any two points from the table and use the slope formula
m = (y2 - y1)/(x2 - x1)
You should find that any two points you pick will lead to a slope of 1. I recommend you try out all possible pairs to help convince yourself the slope is 1.
Steps to solve:
3 < x + 3 < 6
~Subtract 3 to everything
0 < x < 3
Best of Luck!