Linear equations, graphs, slopes, parallels and perpendicula

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Ladyslaw

New member
Joined
Sep 5, 2007
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4
Please help me. I need step by step actions and answers to below problems:

1. Determine whether each ordered pair is a solution of the given equation:
2x - 5y = 0 (-2,0), (-10,6), (5,0)

2. Find the x- intercept and the y- intercept of the graph of the equation:
8x - 11y = 0

3. Find the slope of each line, or state that the slope is undefined:
(-7,6) and (0,4); (-9,-3) and (1,5)

4. Solve the linear equation for y. This will put the equation in the slope-intercept form. Then find the slope and the y- intercept of the line with the equation:
4x + 3y = 4

5. Write an equation in slope-intercept form of the line satisfying the given condition:
The line passes through (-5,6) and is perpendicular to the line that has an x- intercept of 3 and a y- intercept of -9.
 
1)
2x-5y=0
2x=5y
y=.4x

if x=-2 y=-.8 no
if x=-10 y=-4 no
if x=5 y=2 no
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2)
8x-11y=0
8x=11y
y=8/11 x +0 slope 8/11 y intercept 0
set y=0 to find x intercept
then x intercept=0
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3)
the slope is the rise [ difference in y] over the run [ the x distance]
[-7,6] , [0,4]
rise = 6-4
run -7-0
slope= - 2/7

[-9,-3],[1,5]
rise=-3-5
run=-9-1
slope= -8/[-10]
slope=8/10

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4)
y=mx+b is a straight line m is slope and b the y intercept
4x+3y=4
3y=-4x+4
y= [-4/3] x +4/3
slope = -4/3
y intercept = 4/3
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5)
let us find the slope of the line with a x intercept of 3 and a y intercept of -9
the two points are:[0,-9], [ 3,0]
the slope, or rise over run
rise= -9-0
run = 0-3
slope = -9/[-3]
slope = 3

the line of interest is perpindicular to the line with this slope, so its slope is the negative reciprocal
m of line of interest =-1/3

line of interest: y=-1/3 x+b
but the point x=-5 and y=6 is on this line
substitution yields
6=[-1/3][-5] +b
6= 5/3 +b
18/3 -5/3 =b
13/3 =b
y=-1/3 x +13/3 answer or by multiplying
3y=-x+13


please check for math errors
Arthur
 
Thank you, you are such a life saver. It has been awhile and some of the problems give me a bit of a hard time. I appreciate your time and your help.
Thanks,
Ladylaw
 
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