In the equation 2y + px = 5, for what value of p is the graph of the equation parallel to the graph of x + y = 5?
A. 2
B. -2
C. 1
D. -1
2007-03-07 04:18:17 · 5 answers · asked by Anonymous in Science & Mathematics ➔ Mathematics
Paralel means they have the same gradient, express them both in the form y=mx+b
1. y=(-p/2)x +5/2
2. y=-x+5
For these to have the same gradient you gotta make the number besides x the same, that is:
-p/2 = -1
so, p=2
Your answer is A
2007-03-07 04:25:19 · answer #1 · answered by krumenager 3 · 0⤊ 0⤋
the slope of the equation x + y =5 is -1. so you need to find the slope of 2y + px =5 first start by putting the equation in the correct form.
2y= -px + 5
y = (-p/2)x + (5/2)
the slope of the line is -p/2 set that = -1 and p=2. If the slopes are equal it means the lines a parallel
2007-03-07 12:30:50 · answer #2 · answered by semgod 1 · 0⤊ 0⤋
2y + px = 5 will be parallel to x + y = 5 if p = 2, i.e. 2y + 2x = 5 is parallel to x + y = 5
2007-03-07 12:29:48 · answer #3 · answered by Swamy 7 · 0⤊ 0⤋
the answer is 2
if they are parallel, the slopes of the two graphs have to be same
first one: -2/p
second one: -1
-2/p=-1
p=2
note: to find the slope of a graph u divide the negative of coefficient of y to the coefficient of x
2007-03-07 12:34:32 · answer #4 · answered by whatsoever 2 · 0⤊ 0⤋
the answer is A.
2007-03-07 12:27:01 · answer #5 · answered by subhonjon 1 · 0⤊ 0⤋