Line A is perpendicular to the line with the equation y = -x/5 and the

Question

Line A is perpendicular to the line with the equation  y= - \frac{1}{5}x  and the point (3, -10) is on line A. Which of the following is the equation of line A?

A.  y=- \frac{1}{5} x - \frac{47}{5}

B.  y = \frac{1}{5} x -\frac{53}{5}

C.  y = 5x

D.  y=5x - 5

E.  y=5x - 25

gmatzpractice · Answer

E

Slope is 5
Point on the line is (3, -10)

EgmatQuantExpert · Answer

Solution

Given:  
 • Line A is perpendicular to the line with the equation y =  \frac{-1}{5} x
• The point (3, -10) is on line A

To find:  
 • The equation of line A

Approach and Working:   
 • The slope of the line y =  \frac{-1}{5} x is ( \frac{-1}{5} )

If the slope of line A is m, 
 • ( \frac{-1}{5} ) m = -1
Or, m = 5

As line A is passing through the point (3, -10), we can write
 • y = 5x + c
Or, -10 = 5*3 + c
Or, c = -10 – 15 = -25

Therefore, the equation of line A:
 • y = 5x – 25

Hence, the correct answer is option E.

Answer: E

PKN · Answer

Equation of a line passing through point (x,y) and having slope m is:-

y=m*x+c, where c is the y intercept.------------------(1)

Since this line is perpendicular to the line with the equation  y= - \frac{1}{5}x ,

hence slope of the desired line: m* \frac{-1}{5} =-1 or m=5.

Since the desired line passes through point(3,-10), hence this point must satisfy eq(1), we have

-10=5*3+c or c=-25.

So, the desired equation of line is:

y=5x-25

Ans. (E)

GyMrAT · Answer

Given Line A is perpendicular to  y= - \frac{1}{5}x .

Since product slopes of two perpendicular lines =  -1 , we have

Slope of line A  * (-1/5) = -1

Hence slope of line A  = 5

Given that point  (3,-10)  is on line A, we can

Using the equation of line as  (y-y_1) = m(x-x_1)  , where  m = 5  &  x_1 = 3 ,  y_1 = -10

we get,  (y + 10) = 5*(x - 3)

Equation of line A is  y=5x - 25

Answer E.

Thanks,
GyM

bumpbot · Answer

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Line A is perpendicular to the line with the equation y = -x/5 and the

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