Question

Which of the following equations represents a line parallel to 4x - y = -5?
Question 9 options:
8x - 2y = -10
4x + y = -2
4x - y = 2
2x - 1/2y = -5/2

Answer 1

4x - y = -5

put it into slope-intercept form

4x - y = -5
-y = -5 - 4x
y = 4x + 5

since y = mx + b we see that m = 4 and b = 5

for y1 = m1x + b1 and y2 = m2x + b2 to be parallel lines they must satisfy the condition that m1 = m2 and b1 =/= b2 (if the intercepts are equal as well its the same exact line!)

so we need to see which option has a slope equal to 4

testing A:
8x - 2y = -10
-2y = -10 - 8x
y = 4x + 5
while m = 4 which is the same as the given line

B:
4x + y = -2
y = -2 - 4x
m = -4 not 4 so B is disqualified

C:
4x - y = 2
-y = 2 - 4x
y = 4x - 2
m = 4 which is the same as the given line so this is parallel

D:
2x - 1/2y = -5/2
-1/2 y = -5/2 - 2x
-y = -5 - 4x
y = 4x + 5
see the explanation for A

answer is ultimately C buddy

Answer 2

Thanx good explaining by the way ;)