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Write an equation that represents the line.
Use exact numbers.

Write an equation that represents the line. Use exact numbers.-example-1

1 Answer

4 votes

Answer:

y=(7/5)x + 34/5

Explanation:

All straight lines generally follow the equation format of: y=mx+c

Where m is the slope/gradient of the line, and c is a constant, the y-intercept, the y value when x=0.

To start, we need to find the slope, which we do by dividing the rise of the line by the run, that is the difference between the y value of two points divided by the different between the x value of two points.

We can use the two given points on the graph: (-7,-3) and (-2,4).

The rise is 7 because 4-(-3)=7, and the run is 5 because -2-(-7)=5.

Therefore the slope is 7/5.

so our equation so far is:

y=(7/5)x + c, (It is positive because the line is 'going upwards'.)

Now to find the c, we can just substitute in a pair of coordinates, we can use (-2,4):

4= (7/5)(-2) + c

4 = -14/5 + c

4 + 14/5 = c

c= 34/5

Therefore our full equation is:

y=(7/5)x + 34/5

Hope this helped!

User Karmakaze
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