Question

Write the equation of direct variation for x = -5 and y = 90

Answer 1

use y=mx+c
and put the value of x and y in it.....

Answer 2

y=kx

Answer 3

@noniebug you know the equation...so what more help do you need?

Answer 4

just substitute x and y

Answer 5

how to plug it in :(

Answer 6

what is y?

Answer 7

umm 90.

Answer 8

good so put that instead of y

90 = kx

now can you do that to x?

Answer 9

y=(90/-5)?

Answer 10

nope..remember y is 90..you shouldnt have a y

Answer 11

wtf? um, k=90/-5 so k=-18?

Answer 12

hmm close..remember i wrote 90 = kx

Answer 13

all that's left is to substitute x

Answer 14

so it should be in the form 90 = kx still

Answer 15

-18/-5?

Answer 16

hmm let's dothis step by step

we have 90 = kx

what is x?

Answer 17

this is beyondd sooooo confusing.

Answer 18

yes lets do that!

Answer 19

okay let's begin from start...equation for direct variation is y = kx right?

Answer 20

yess.

Answer 21

then y = 90 so we substitute 90 into the y of y = kx

so we get 90 = kx

got it?

Answer 22

yeahh gotchaa.

Answer 23

now what is the value of x?

Answer 24

-5?

Answer 25

good..so how will the equation look like if we substitute x with -5 in

90 = kx?

Answer 26

uhh.. 90=k (-5)?

Answer 27

yup!!! you got it :D

so equation is simply 90 = -5k

Answer 28

i just put -5 in front of k..