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#1 2005-11-19 05:06:03
- Sarah
- Guest
equations
Hello there,
I really need your help 
the lines px + 4y - 2 = 0 and 2x - y + p = 0 are perpendicular. Find the value of p.
The lines x+2y+12=0, x-2y+3=0, 2y+x-8=0 and x-2y-2=0 form a quadrilateral. What is the best description for this quadrilateral?
I really feel stupid :-|
thank you so muchhh!!!
#2 2005-11-19 05:40:53
- austin81
- Member
- Registered: 2005-03-21
- Posts: 39
Re: equations
Two lines are perpendicular if the product of their gradients equals -1
Write each equation in the form y=mx+c:
where m is the gradient.
px+4y-2=0
y=-(p/4)x+1/2......., m1=-p/4
2x-y+p=0
y=2x+p.........., m2=2
m1*m2=-1...., (-p/4)*2=-1....p=2
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