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Write the equation of a line in slope-intercept form that passes through (2,6) and (-1,-4)

User Connell
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1 Answer

4 votes

Answer:

y = 10x/3 - 2/3

Explanation:

First, find the slope using the slope formula:

m=(y2-y1)/(x2-x1) ==> Slope is the change in y over the change in x: (Δy/Δx)

(x1, y1), (x2, y2) ==> (x1=2, y1=6), (x2=-1, y2=-4) <== (2, 6), (-1, -4)

m=(-4-6)/(-1-2) ==> plugin (x1=2, y1=6), (x2=-1, y2=-4)

m=(-10)/(-3) ==> simplify

m=10/3

Now plugin the slope into the slope-intercept form equation y=mx+b:

y = 10x/3 + b

6 = 10(2)/3 + b ==> plugin the point (2, 6) into the x and y values, (x=2, y=6).

6 = 20/3 + b ==> simplify

(6 = 20/3 + b)*3 ==> multiply the equation by 3 to remove fractions

18 = 20 + 3b ==> simplify

Now solve for b:

-2 = 3b ==> subtract 20 on both sides to isolate b

3b = -2

b = -2/3 ==> divide 3 on both sides

y = 10x/3 + (-2/3) ==> plugin b = -2/3 into the slope-intercept form equation

Answer:

y = 10x/3 - 2/3 =>adding a negative number is equivalent to subtracting the

positive number

User Raffaeu
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8.2k points