In the coordinate plane, the y-intercept of the line k is equal to twi

Question

In the coordinate plane, the y-intercept of the line  k  is equal to twice its slope. The y-intercept is not  0 . What is the x-intercept of the line  k ?

A. -2  
 B. -1  
 C. 0  
 D. 1  
 E. 2

BrentGMATPrepNow · Accepted Answer

One approach is to  choose some values  that meet the given information.

In the coordinate plane, the y-intercept of the line k is equal to twice its slope.   
Okay, so let's say the y-intercept of line k is 6. We get: 
 https://i.imgur.com/qJ5GeRQ.png

Since the y-intercept (6) is TWICE the slope, we know that the slope = 3
 https://i.imgur.com/DtYOEiZ.png

What is the x-intercept of the line k?  
Since   (x, 0)   are the coordinates of the x-intercept . . . 
 https://i.imgur.com/z68tiuE.png 
. . . we can apply the slope formula to wrote: ( 6  -   0  )/( 0  -   x  ) = 3
Simplify: 6/(-x) = 3
Multiply both sides by -x to get: 6 = -3x
Solve: x = 6/(-3) = -2

Answer: A

Cheers,
Brent

Archit3110 · Answer

given c=2m

y=mx+c
or say
y=mx+2m
x= y/m-2

since y is not =0 , x intercept would be -2 ..
IMO A

fskilnik · Answer

k\,\,\,:\,\,\,y = ax + 2a\,\,\,\,\,\,\left( {a 
e 0} ight)\,\,\,\,\,\,\left( * ight)

?\,\,\,\,:\,\,\,{x_p}\,\,{m{when}}\,\,y = 0

\left( * ight)\,\,\,\, \Rightarrow \,\,\,\,\,\,0 = a\left( {{x_p} + 2} ight)\,\,\,\,\,\,\,\mathop \Rightarrow \limits^{a 
e 0} \,\,\,\,\,\,\,? = {x_p} = - 2

This solution follows the notations and rationale taught in the GMATH method.

Regards, 
Fabio.

shashankism · Answer

Equation of a line is y = mx +c
Since y intercept = twice of slope
So, c = 2m
y=mx+2m

TO find x intercept lets put y = 0 
SO, mx+2m = 0 
-> x = -2

Answer A

MathRevolution · Answer

=>

The equation of line  k  has the form,  y = mx + b , where  m  is the slope and  b  is the y-intercept.

Let  m  be the slope of line  k . Then  b = 2m , and the equation is  y = mx + 2m = m(x+2). 
The x-intercept of line  k  is  -2,  since  -2  is a root of  m(x+2)=0.

Therefore, the answer is A.
Answer: A

ScottTargetTestPrep · Answer

We can let m = the slope, and thus 2m = the y-intercept. The equation of the line is

y = mx + 2m

To find the x-intercept, we set y = 0 and solve for x. Thus, we have:

0 = mx + 2m

-mx = 2m

Since the y-intercept is non-zero, m is non-zero as well. Thus, we can divide each side by -m:

x = 2m/(-m)

x = 2/(-1) = -2

Answer: A

pravalithota · Answer

slope, m=-y/x (1)
Given, y=2m (2)
sustitute (2) in (1),
m=-2m/x
ie., x=-2

answer is A

Fdambro294 · Answer

Slope of a line is given by:

(-) (Y-intercept) / (X-intercept)

Let the x-intercept = a

Let the y-intercept = b

m = (-b) / (a)

And

b = 2m

b = 2 * (-b / a)

Since the y-intercept is not 0, the line does not pass through the origin, resulting in the x-intercept (a) being non-zero as well

Cancel the b variable in the numerator and cross multiply:

1 = -2 / a

a = -2

Answer *A*
-2

Posted from my mobile device

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In the coordinate plane, the y-intercept of the line k is equal to twi

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