Question

I just have this last one @zilchero
What is the slope of the line whose equation is –48 = 2x − 8y?

Answer 1

y = mx + b

get the equation into that form first

Answer 2

-48=2x+8
????????????????????

Answer 3

Still there @zilchero?

Answer 4

yes, but this thing has been glitching, so it's hard to type anything before i'm bumped back to the home page

you cannot just erase variables.

let's do some moving around

-48 = 2x - 8y

do you know how to move terms around?
to get to
8y = 2x + 48
?

Answer 5

commutative property?

Answer 6

Uh, sort of.

I'll show you an example:
5 + x = 8

you need to get x alone on one side, so you need to get rid of the 5. but how?
how do you get 5 to go away? subtract five. But since you do one thing to one side, you have to do the same thing to the other.

5 - 5 + x = 8 - 5

0 + x = 3

x = 3

that can be done with multiple variables as well

-48 = 2x - 8y

we want to isolate y this time, because y = mx + b

let's get rid of 2x by subtracting 2x from both sides

-48 - 2x = 2x - 2x - 8y
-48 - 2x = 0 - 8y

i think we can agree that 2 + 2 = 3 + 1 can also be written as 3 + 1 = 2 + 2.
All i did was flip it.
I'm going to do the same thing for -48 - 2x = 0 - 8y, since the concept is the same

-8y = -2x -48

remember to keep the signs! anything that has a negative (or a minus sign) in front of it must be negative!

i'll continue the problem in another post

Answer 7

-8y = -2x - 48

we need to get y alone, as I said. So we need to get rid of the -8 in front of it.
how? by dividing by eight.
-8y is the same thing as -8 times y
-8 divided by -8 is one, which means we got rid of the -8
so we need to divide by eight ON BOTH SIDES, because what you do to one side you must do to the other.

-8y/-8 = -2/-8(x) - 48/-8

Answer 8

can you simplify that for me?

Answer 9

I think so hold on a sec

Answer 10

-2/ -8(x) - 40???

Answer 11

where did the y go?

Answer 12

-2y

Answer 13

Okay, wait a second

Answer 14

how about now?