Parallel Lines

[dev.gavande]

Which of the following lines is parallel to line x = 1.44 - 3y ?

[A]y = x/6 + 25
y = 0.48 - x/3
[C]x/3 - y = 2
[D]y + x/3 = 10
[E]x/4 + 3y = 1

I don't understand how to solve this?

[Anurag@Gurome]

Which of the following lines is parallel to line x = 1.44 - 3y ?

[A]y = x/6 + 25
y = 0.48 - x/3
[C]x/3 - y = 2
[D]y + x/3 = 10
[E]x/4 + 3y = 1

I don't understand how to solve this?

Parallel lines have the same slope.
x = 1.44 - 3y implies 3y = 1.44 - x or y = -x/3 + 1.44/3 = -x/3 + 0.48, which implies that slope of x = 1.44 - 3y is -1/3
Now look at the given options to check which line has a slope of -1/3.
[A]y = x/6 + 25; slope = 1/6
y = 0.48 - x/3; slope = -1/3, here the equation of the line is the same as the given equation so both the lines are the same.
[C]x/3 - y = 2; slope = 1/3
[D]y + x/3 = 10; slope = -1/3 implies this line is parallel to the given line.
[E]x/4 + 3y = 1, slope = -1/12

The correct answer is D.

[shankar.ashwin]

For 2 lines to be parallel they should have equal slopes.

Express each eq. in the form y =mx + c

m is the slope.

Only and [D] have the same slope (-1/3)

But is the same eq. as the question, so the 2 lines would be collinear

Hence d

[dev.gavande]

Thanks Anurag and Shankar!!
I got it now..