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Please help me solve this

Please help me solve this-example-1
User GrahamS
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2 Answers

7 votes

Answer:
y= 1/4x + 20

Explanation:

To find rate of change, there is an equation. (there is an equation for everything :) ).

The equation is:
y2-y1/x2-x1

Now, if you are confused, I am here to explain. Y2 means The y value of the second y point.

In the graph, the second point point is (8,22) (remember, x always comes first!).

Now you need to get the y value, which is 22.

Next, you need to find Y1. The number after y means the point. Y2 means the second point whereas Y1 means the first point.

Y1 = 21 (look at ex. above if needed)

Now you need to find x

Just do the same thing with the y values, but use the x value instead :).

X1= 4

X2= 8

Now you have formed your equation to find the rate of change

22-21/8-4

1/4 is the rate of change.

Or, there is a simpler method called "Rise Over Run".

Basically, you have to see how much the y value rises. Y is the rise, x is the run.

(ex. 21 to 22 (first 2 points) rises 1)

(ex. for X, 4 goes up 4 to get 8)

Now you have two numbers: 1 and 4

Just divide: 1/4 = 1/4 (obviously.)

Now there is also an equation format to help you to form the equation!

That is:
y=mx+b

Now, Y is what you are solving for, m is the slope (or rate of change), x is the x value, and b is the y intercept.

So m, the rate of change, is what we have already solved for!

m= 1/4

y=1/4x+b

B is the slope intercept

It is the point that crosses the Y axis.

Which, in this case, is 20.

So, the equation is
y=1/4x +20

Hope this helps!

-jp524

User Andy Lester
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5.0k points
3 votes
The equation would be in the format y=mx+b, m=rise/run=1/4 and b=y-intercept=20 Y=1/4x+20.
User Xbrady
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4.9k points