Question

Find the value of k so that the graph of 8y +kx=4 and the line containing the point (5,-8) ans (2,4) are parallel

Answer 1

What is the slope of the line through the given two points?

Answer 2

i didnt get one

Answer 3

Slope of the line through two points = \(\Large\frac{y_2-y_1}{x_2-x_1} \)

Answer 4

-4

Answer 5

the other is -8

Answer 6

??

Answer 7

Correct.

What is the slope of the line 8y +kx=4 in terms of k?
Put it in the slope-intercept form first (that is, y = mx + b)

Answer 8

The -4 is correct for the slope of the line through the given two points.

Answer 9

not sure what to do

Answer 10

8y + kx = 4
Yo find the slope of the above line, put it in slope-intercept form:
subtract kx
8y = -kx + 4
divide by 8
y = -k/8 * x + 4/8
The coefficient of the x-term is the slope.
slope = -k/8

Slope of the line through (5,-8) and (2,4) is -4

Since the two lines are parallel, their slopes must be the same.

-k/8 = -4
-k = -32
k = 32

Answer 11

oooohhhh i usually do -a/b from standard form to get slope i put -1 instead of -k

Answer 12

Yes, if you know how to calculate slope directly from the standard form you can skip that step. But most students are familiar with finding slope from the slope-intercept form.

Answer 13

Here a = k and b = 8
slope = -a/b = -k/8 (same as what I got above)

Answer 14

a is the coefficient of x and b is the coefficient of y in the standard form.

Answer 15

yup i just saw that, the x and y where switched

Answer 16

yeah, got to watch out for such things.

Answer 17

yea do we ever need to find c

Answer 18

i haven't seen a problem like that

Answer 19

by "c" do you mean the y-intercept?

Answer 20

Ax+bx=c

Answer 21

8y +kx=4. Here c is already known. It is 4. So not needed here.

Answer 22

ok i get it, here another problem easy but i dont get the concept since i get another solution

Answer 23

one maid clean the house in 6 hours. another maid can do the job in 5 hours. how long will it take them to do the working job together.

Answer 24

30/11

Answer 25

correct.

Answer 26

but i thought it was like this 1/5+1/6

Answer 27

Both are true.

In 1 hour, the first maid can clean 1/6th of the house.
In 1 hour, the second maid can clean 1/5th of the house.

If they work together, then in 1 hour they can clean (1/6 + 1/5)th of the house
Or (11/30)th of the house.
So to clean the whole house it will take 30/11 hours.

Answer 28

11/30 th of the house takes 1 hour
1 house will take 1 * 1 divided by 11/30 or 30/11 hours.

Answer 29

If 1/4th of the house can be cleaned in 1 hour, then the house will take 4 hours.
If 1/13th of the house can be cleaned in 1 hour, then the house will take 13 hours.
If 1/x th of the house can be cleaned in 1 hour, then the house will take x hours.
If p/q th of the house can be cleaned in 1 hour, then the house will take q/p hours.
If 11/30 th of the house can be cleaned in 1 hour, then the house will take 30/11 hours.

Answer 30

ok that make sense

Answer 31

alright.

Answer 32

thank you

Answer 33

you are welcome.