Which of these are parallel or perpendicular? ?

Question

i can not figure this out! i have been searching to figure these out for an hour and i can't. can someone please help me ?? :]

which of these equations are parallel or perpendicular? please show work if it was necessary. thank you !

** the answer may be both for some of them.

1. y=1/3x+6 ***1/3 is a fraction.

2. y=3x-8

3. y=-3x+7

4. y=-1/3x-2 *** -1/3 is a fraction.

5. y=1/3x ***1/3 is a fraction.

Answer 1

All of the equations you show are in slope-intercept form

y = mx + b

So, you should be able to "read" the slope of each line.

Next, you need to know what property of slope(s) makes line perpendicular or parallel.  You also need to be comparing two lines (equations) when determining whether they are parallel or perpendicular.  Your question does not make clear what is being compared.

Two lines are parallel when they have the SAME slope.  

Two lines are perpendicular when the product of their slopes = -1

m1 * m2 = -1

Another way is to say that their slopes are the opposite reciprocals or negative inverses of each other.  You should be familiar with those terms.  Lines that are vertical and horizontal are special cases.

You now have enough information to analyze your problem.

Answer 2

Parallel or perpendicular to what?  To each other?  

Answer 3

http://www.webmath.com/

Answer 4

For two lines to be parallel, they need to have the same slope and a different y-intercept:

Since lines 1 and 5 both have a slope of 1/3 and each has a different y-intercept (6 versus 0), they are parallel.

For two lines to be perpendicular, the slope of one line must be the negative reciprocal of the other line's slope. (Take 1 over the slope and negate it.)

Since line 4 has a slope (-1/3) which is the negative reciprocal of line 2's slope (3), those two lines are perpendicular.

Line 1's slope (1/3) and line 3's slope (-3) are also negative reciprocals of each other so those two lines are perpendicular as well.

[added]

Sorry, I missed one. Since lines 1 and 5 are parallel, lines 3 and 5 are perpendicular to each other as well.

Answer 5

graph them on one graph

or plug em in a calculator..

Answer 6

parallel lines will have the same slope, and perpendicular lines will have a product of -1 when you multiply their slopes

1. slope = 1/3

2. slope = 3

3. slope = -3, which is the inverse of #1 and #5, so it is perpendicular to #1 and #5

4. slope = -1/3, which is the inverse of #2

5. slope = 1/3, which is the same as #1, so it is parallel to #1

Answer 7

find the derivation of all of them, the derivation y is equal to the slope.

if two slopes are equal then their lines are parallel, if a slope is equal to the reverse of an other slope and multiplied by minus one then their lines are perpendicular.