First you want to divide $90 by four. You want to take the answer and divide it by 2.
$90 / 4 = $22.5
22.5 / 2 = Mrs. Jackson saved $11.25.
You've got five different problems in this photo ... four on top and the word problem on the bottom ... and they're all exactly the same thing: Taking two points and finding the slope of the line that goes through them.
In every case, the procedure is the same.
If the two points are (x₁ , y₁) and (x₂ , y₂) , then
the slope of the line that goes through them is
Slope = (y₂ - y₁) / (x₂ - x₁) .
This is important, and you should memorize it.
#1). (8, 10) and (-7, 14)
Slope = (14 - 10) / (-7 - 8) = 4 / -15
#2). (-3, 1) and (-17, 2)
Slope = (2 - 1) / (-17 - -3) = (2 - 1) / (-17 + 3) = 1 / -14
#3). (-20, -4) and (-12, -10)
Slope = [ -10 - (-4) ] / [ -12 - (-20) ]
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The word problem:
This question only gives you one point on the graph,
and then it wants to know what's the slope ?
What are you going to do for another point ?
A "proportional relationship" always passes through the origin,
so another point on the line is (0, 0) .
Now you have two points on THAT line too, and you can easily
find its slope.
The question did not spesify the stating value for n.
Assuming, n = 0 is the starting value.
1st term is when n = 0:
f(0) = (0)^2 - 5 = 0 - 5 = -5
2nd term: f(1) = (1)^2 - 5 = 1 - 5 = -4
3rd term: f(2) = (2)^2 - 5 = 4 - 5 = -1
4th term: f(3) = (3)^2 - 5 = 9 - 5 = 4
Therefore, the first 4 terms are: -5, -4, -1, 4.
I believe your answer is D, scatterplot. hope this helps
