Question

write an equation of the line containing the given point and perpendicular to the given line
(6,8)9x+y=3

Answer 1

While parallel lines have the same slope, perpendicular have negative reciprocals:
The first line can be written as y = -9x + 3
that means the perpendicular line must have a slope of 1/9
y = 1/9x + b
substituting in the point:
8 = 1/9 (6) + b
8 = 2/3 + b
b = 22/3
y = 1/9x + 22/3

Answer 2

how about this one (4,-5)9x+8y=3??

Answer 3

perpendicular or parallel?

Answer 4

perpendicular

Answer 5

First you need to write the first equation in y=mx+b form to find the slope:
9x+8y=3
8y=-9x+3
y=-9/8x+3/8
Then what did I say about the slope of a perpendicular line?

Answer 6

it must have a slope

Answer 7

but what must be true about that slope and the slope of the line it's perpendicular to?

Answer 8

y=mx+b

Answer 9

that's the slope intercept form, but the slope of a perpendicular line is always the negative reciprocal:
The slope of the first line is -9/8 so the slope of the perpendicular line is 8/9
y=8/9x+b and then plug in the point:
-5=8/9(4) + b
-5 = 32/9 + b
-77/9 = b
y = 8/9x - 77/9