Question

Which function has the greatest rate of change?

A.
6x – 7y = 21

B.
y = 2x – 2

C.
x y
2 7
3 13
4 19


D.
http://static.k12.com/calms_media/media/1523000_1523500/1523241/1/0e13f22fd8434ba8776b9a5e59dab888deeef694/MS_IMC-1400831-161106.jpg

Answer 1

@DanJS

Answer 2

I think it's A

Answer 3

I can help you with this - but I am not going to give the answer.

Do oyu know about gradient of straight line?

Answer 4

I cant say i do.

Answer 5

But i know C is 6

Answer 6

how do you know c is 6 if you don't know what the gradient is?

Answer 7

Because

Answer 8

Right?

Answer 9

so - you DO know that it is 'change in y/change in x'

Answer 10

Yeah i just didn't know it was called a gradient sorry.

Answer 11

in an equation of form
y=mx+b
the value m is the gradient

rearrange a to that form
b is already in that form
c you hve already done
d is a graph so work out gradient from 2 points on the graph

Answer 12

Ok i really only know how to do it on a chart I'm not the best at math could you elaborate how to solve A and D?

Answer 13

btw 'gradient' and 'rate of change' are the same thing

Answer 14

you need to rearrange the equation a so that it is
y = .....

first subtract 6x from EACH side

THEN divide each side by -7

Answer 15

for d choose 2 points on the line

(I suggest (2,5) and (-1,-4)

and do the same calculation as you did for c

Answer 16

I got 15 for A and -1 for C so my answer would be A?

Answer 17

your answer for a is not correct
have you worked out d

as I said - I am not going to give the answer

you need to WORK out (not guess) the gradient for each option, and find the largest

Answer 18

you said above that c is 6
THEN you said it is -1
your first answer for c is correct

Answer 19

I didn't guess sheesh sorry

Answer 20

Oh i meant D sorry

Answer 21

I just mistyped

Answer 22

I see oyu meant D

but you have not done th ecalculation properly

it is (y2-y1)/(x2-x1)

you have used the wrong numbers in that calculaiton

Answer 23

you will get the gradient of a by rearranging it to y=....

for b the equation y = 2x -2 is of the form y = mx+b
the value of m is the gradient (and is 2 in this case)

for c you have calculated that the gradient is 6 by using (y2-y1)/(x2-x1)

for d you can use (y2-y1)/(x2-x1), but you need to use the right numbers. The 2 points are (2,5) and (-1,-4)

When you have the 4 values for gradient you can see whichj is greatest
(hint - it is not a)

Answer 24

Ok So i have 6 for c I think i have 0 for B i have - 1 for D and idk what A is but from you info i think my answer is C

Answer 25

@DanJS