SOLUTION: which line is parallel to y=-5/2x-7 a. 5x+2y+4 b. 2x-5y=30 c.2x+5y=-5 d.5x-2y=8

Algebra ->  Angles -> SOLUTION: which line is parallel to y=-5/2x-7 a. 5x+2y+4 b. 2x-5y=30 c.2x+5y=-5 d.5x-2y=8      Log On


   

Question 1168564: which line is parallel to y=-5/2x-7
a. 5x+2y+4
b. 2x-5y=30
c.2x+5y=-5
d.5x-2y=8
Found 2 solutions by josgarithmetic, AnlytcPhil:
Answer by josgarithmetic(39623) About Me  (Show Source):
You can put this solution on YOUR website!
You want to find which one or ones have same slope as the given equation but not the same y-axis intercept.

LOOK! Your choices are in standard form.
Ax%2BBy=C
By=-Ax%2BC
y=-%28A%2FB%29x%2BC%2FB-----------slope-intercept form, showing slope and y-axis intercept

You see what to do? But you can start with YOUR given equation and work the other way.

Answer by AnlytcPhil(1807) About Me  (Show Source):
You can put this solution on YOUR website!

y=expr%28-5%2F2%29x-7
The given line is in slope-intercept form, y=mx+b, so m=-5/2, which is the
slope of the line, [and b means that the y-intercept is the point (0,-7), which
we don't need here.]

We have to put every one of those 4 lines in slope-intercept form to see
which one has the same slope m=-5/2.

I'll do one for you. You do the other 3.

I'll do d:

2x%2B5y=-5

Add -2x to both sides:

5y=-2x-5

Divide every number by 5:

expr%285%2F5%29y=expr%28%28-2%29%2F5%29x-5%2F5

Simplify:

1y=expr%28-2%2F5%29x-1

y=expr%28-2%2F5%29x-1

Now that equation d. is in slope-intercept form and the slope is m=-2/5, which
is NOT -5/2.  Now you do the others the same way and find the one which does
have a slope of m=-5/2. 

Hmm! I just noticed that you mistyped a. because there is no " = " sign!   

Edwin