are the graphs parallel,perpendicular or neither 5x+8y=7 and 8x-5y=4?

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are the graphs parallel,perpendicular or neither 5x+8y=7 and 8x-5y=4?

2006-07-03 04:57:03 · 2 answers · asked by cityturtleblue 2 in Education & Reference ➔ Other - Education

2 answers

The slope for 5x+8y=7 is -5/8. The slope for 8x-5y=4 is 8/5. The product of the two slopes is -1; therefore, the two lines are perpendicular.

2006-07-03 05:05:10 · answer #1 · answered by Vanessa 4 · 1⤊ 0⤋

5x+8y=7 & 8x-5y=4

8y=-5x+7
y=(-5/8)*y +(7/8)

8x=5y+4
5y=8x-4
y=(8/5)x-(4/5)
--------------
y=(-5/8)*y +(7/8)
slope=m1= -5/8
y=(8/5)x-(4/5)
slope=m2=8/5
---They are perpendicular because
m1= - 1/m2

2006-07-03 05:06:00 · answer #2 · answered by JosyMaude 3 · 0⤊ 0⤋