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Find an equation of the line passing through the given points (1,-3) and (3,3)

User Andreak
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1 Answer

4 votes

ANSWER: y= 3x - 6

Explanation:

(1,-3) and (3,3)

X1=1 X2=3

Y1= - 3 Y2=3

1) Find the slope of the line.

To find the slope of the line passing through these two points we need to use the slope formula:

m =
(Y2-Y1)/(X2-X1)

m=
(3-(-3))/(3-1) m=
(6)/(2) = 3

2)Use the slope to find the y-intercept.

Now that we know the slope of the line is 3 we can plug the slope into the equation and we get:

y= 3x+b

Next choose one of the two point to plug in for the values of x and y. It does not matter which one of the two points you choose because you should get the same answer in either case. I generally just choose the first point listed so I don’t have to worry about which one I should choose.

y= 3x+b point (1,-3)

-3= 3(1) + b

-3-3=b

-6=b

3)Write the answer.

Using the slope of 3 and the y-intercept of -6 the answer is:

y = 3x - 6

User Mesosteros
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5.1k points