A line that passes through (1, 4) and (3, k) has a slope = k. What

Question

A line that passes through (–1, –4) and (3, k) has a slope = k. What is the value of k?

(A) 3/4
(B) 1
(C) 4/3
(D) 2
(E) 7/2

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Official Answer

C

BrentGMATPrepNow · Accepted Answer

Slope of line between the points (x1, y1) and (x2, y2) = (y2 - y1)/(x2 - x1) 
So, we can write: k =  / 
Simplify: (k + 4)/4 = k
Multiply both sides by 4 to get: k + 4 = 4k
Subtract k from both sides to get: 4 = 3k
Divide both sides by 3 to get: 4/3 = k

Answer: C

Cheers,
Brent

Vips0000 · Answer

Slope = (y2-y1)/(x2-x1)
=> k = (k+4)/(3+1)
=> 4k = k+4
=> k =4/3

Ans C it is!

rajathpanta · Answer

y=mx+c is the equation. Since the line passes through (-1,-4) and (3,k) substitute this for the value of x and y.

we get 2 equations

-4=-k+c...(1)
c=-2k.......(2)

Substitute for C in equation 1. we get k=4/3.

The ans is C.

mbaiseasy · Answer

A line that passes through (–1, –4) and (3, k) has a slope = k. What is the value of k?

m =  \frac{y2-y1}{x2-x1} 
m =  \frac{k-(-4)}{3-(-1)}

m =  \frac{k+4}{4}  &  m = k

k = \frac{k+4}{4} 
 4k = k+4 
 k = 4/3

Answer: 4/3

vasili · Answer

(k+4)/(3+1)=(k+4)/4 this is the slope of the line

we also know that slope=k, then respectively

k=(k+4)/4
4k=k+4
k=4/3

Answ C

mehrdadtaheri92 · Answer

Answer Is C....

Since 2 points are given and we are told that a line passes through points (-1, -4) & ( 3,k) , so we have simple formula to line's slope.

slope = ( y2- y1)/ (x2-x1) Or : ( k-(-4) ) / ( 3-(-1)) = k+4/ 4 and we are told that this is equal to k

so we have : k+4/4 =k and multiple both sides by 4 and get : k+4 = 4k or 3 k=4 so , k= 4/3 answer c...

Bunuel · Answer

MAGOOSH OFFICIAL SOLUTION:

This is a considerably more difficult one, which will involve some algebra. Let’s say that the “first” point is (–1, –4) and the “second,” (3, k). The rise = k + 4, which involves a variable. The run = 3 – (–1) = 4. There the slope is (k + 4)/4, and we can set this equal to k and solve for k.
(k + 4)/4 = k
k + 4 = 4k
4 = 3k
k = 4/3

Answer = C

LogicGuru1 · Answer

Slope = Delta y/Delta x
 k=\frac{k-(-4)}{3-(-1)} ===>k= \frac{k+4}{4} ===>4k=k+4 ==>3k=4 therefore  k=\frac{4}{3}

Answer C

bumpbot · Answer

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A line that passes through (1, 4) and (3, k) has a slope = k. What

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A line that passes through (1, 4) and (3, k) has a slope = k. What

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