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**Sarah****Guest**

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!!!

**austin81****Member**- Registered: 2005-03-21
- Posts: 39

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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