Determine which two equations represent parallel lines.?

Question

Determine which two equations represent parallel lines.
(a) y = –8x + 4 (b) y = 8x + 4 (c) y = 1/8x + 4
(d) y = –8x + 6

A) (a) and (b)
B) (b) and (c)
C) (a) and (c)
D) (a) and (d)

Write the equation of the line with slope 4 and y-intercept (0, –5).

school year round. practice questions. totally lost!

Answer 1

D because the both have a slope of -8

y=mx+b where m is slope an b is yintercept
So y= 4x - 5

Answer 2

Parallel lines are lines with the same slope...so in the slope intercept form (y = mx + b) you are looking form the same # as the m.
SO...your answer is D)(a) and (d) because the -8 is the same...

For the second one:
in the equation y = mx + b
m = slope
b = y-intercept
SO...given: slope 4 and y-intercept (0, -5)
m = 4
b = -5
So, the equation is: y = 4x + (-5) aka: y = 4x - 5

Answer 3

Keep working at it, you'll see, you'll get it eventually.

To be parallel, lines have to have the same slope. The slope is determined by the number multiplying x.

The slope in:
a is -8
b is 8
c is 1/8
d is -8

so you can see that a and d have the same slope.


and for the secone one:

slope, as mentionned above, is the number that multiplies x. and the other number in the equation will determine where the line intercepts the y axis; in this case, at -5

so
y=4x-5

not sure? plug in x=0 and you get y=-5: coordinates 0,-5

Answer 4

D

since slopes of both are -8

y=4x-5

since the general equaton for the line is y=mx+b where m is slope , so plug poin (0,-5) to get b=-5

Answer 5

parallel line have the same slope..so a and d have slope = -8.
m=4..b=-5 ..so y=4x-5

Answer 6

When the slope (or the number in front of x) is the same in both equations, they are parallel. Therefore, a (y=6x-10) and c (y=6x+5) are parallel because the slope is 6.

Answer 7

Look for the two equations that have the same slope. Same slope = parallel. Negative reciprocal slope = perpendicular.

a and d are parallel.