Write an equation in standard form of the line that contains the points (-2,3) and is parallel to the like y=8x+4 and perpendicular to the line y=8x+4

Question

White of the following is parallel to the line y=8x+4 and contains the points (-2,3).

a. 8x+y=19

b. X+y=5/8

c. X-y=-5/8

d. 8x-y=-19

Answer 1

Which of the following is parallel to the line y=8x+4 and contains the points (-2,3)?
a. 8x+y=19
b. X+y=5/8
c. X-y=-5/8
d. 8x-y=-19

 

Parallel lines have the same slope...

Given y = 8x + 4 which is in slope intercept form of y = mx + b where slope is m..

The slope is 8.  Any line parallel to this must have a slope of 8

 

a.  8x + y = 19 ...    y = -8x + 19     slope is -8

 

b.  x + y = 5/8  ... y = -x + 5/8        slope is -1

 

c.  x - y = -5/8 ...  y = x + 5/8         slope is 1

 

d.  8x - y = -19 ...  y = 8x + 19        slope is 8

 

The only choice which has the same slope is the 4th equation so it is the only

one parallel to the given line.

 

Check the point (-2, 3)

y = 8x + 19

3 = 8(-2) + 19

3 = -16 + 19

3 = 3

The equation balances so the point (-2, 3) is on the line.