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PLZ HELP!!!! Explain 72. Determine the value of r so that a line through the points with the coordinates (r, 4) and (-2,3) has

slope 1/4
a. 4.5
b. 6
c. -2
d. 2

User Will Stern
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1 Answer

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Answer:

d. 2

Explanation:

The point-slope form of the equation for the line can make use of the given slope and point:

y -k = m(x -h) . . . . . line with slope m through point (h, k)

y -3 = 1/4(x +2) . . . . line with slope 1/4 through point (-2, 3)

Filling in the unknown point values, we have ...

4 -3 = 1/4(r +2)

4 = r + 2

2 = r

_____

Alternate solution

The way the question is worded, you seem to be expected to use the slope formula.

m = (y2 -y1)/(x2 -x1)

For the given points and slope, you have ...

1/4 = (3 -4)/(-2 -r)

-2 -r = 4(-1) . . . cross multiply

2 = r . . . . . . . . add r+4 to both sides

PLZ HELP!!!! Explain 72. Determine the value of r so that a line through the points-example-1
User RomanKovalev
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