if the slope of line p is 1/5 and the slope of line q is -5, then what is true abou the lines p and q (assume lines p and q are coplanar)?

Question

anonymous · Answer

they are parallel 
they are perpendicular 
they are neither parallel nor perpendicular 
they are skew lines

whpalmer4 · Answer

parallel lines have the same slope
perpendicular lines have slopes whose product is -1

anonymous · Answer

so is it A?

whpalmer4 · Answer

isn't A "they are parallel"?  Doesn't the problem say that one line has slope 1/5 and the other line has slope -5?  Didn't I say parallel lines have the same slope?  Are 1/5 and -5 the same?

anonymous · Answer

yeah

anonymous · Answer

-5=1/5

whpalmer4 · Answer

-5 does not equal 1/5!!!

anonymous · Answer

oh ok so its not A either then what is it

whpalmer4 · Answer

are we writing your name on the paper, or mine? :-)

whpalmer4 · Answer

what is -5 * 1/5?

anonymous · Answer

1?

whpalmer4 · Answer

5 * 1/5 = 1

-5 * 1/5 = ?

whpalmer4 · Answer

a negative number * a positive number gives you a negative number
a negative number * a negative number gives you a positive number
a positive number * a positive number gives you a positive number

whpalmer4 · Answer

-5 * 1/5 = -1

as I mentioned earlier, if two lines' slopes multiplied together give you -1, the lines are perpendicular

anonymous · Answer

oh so b?

whpalmer4 · Answer

if b is the answer that says they are perpendicular, then yes

anonymous · Answer

thnx and sorry im so stupid XD

whpalmer4 · Answer

not stupid, just more room for improvement :-)