Question

How Can I solve this using y=mx+b

Answer 1

How can I sovle this

Do i need to use y=mx+b?

Answer 2

anyone?

Answer 3

you don't need to use that here

Answer 4

The beginning is when x = 0

Answer 5

So what is y when x = 0?

Answer 6

you just need to read the value of y when x=0 and then work out the slope of the line

Answer 7

I dont understand

Answer 8

Why does x = zero ?

Answer 9

That signifies the beginning of summer

Answer 10

I got the rate -3/10 now how can I make it into an equation of y=mx+b

Answer 11

The y-intercept which is b = 20 \
but how do I get the rest

Answer 12

y=mx+20

Answer 13

The rate is visually represented by the slope

Answer 14

The steeper the slope, the greater the rate of change

Answer 15

So

\[\Large y = mx+b\]

becomes

\[\Large y = -\frac{3}{10}x+20\]

because the slope is 'm' and the y-intercept is b

Answer 16

OOOOOOooHHHH

Answer 17

In this case, m = -3/10 and b = 20 (which is what you found)

Answer 18

yea now we need x and y

Answer 19

if you just want to solve a) and b), then all you need is the y intercept (for part a) and the slope (for part b)...you don't need to find anything else

Answer 20

this equation we found is also extra info (probably useful for answering other questions that are related to this problem...but not parts a and b)

Answer 21

Just for curisoty is this the proper equation of the line or do we alsp need the x and y values

Answer 22

This is the equation of the line in slope-intercept form

The values of x and y are variables...so they'll change (and not be fixed values)

Answer 23

For instance, when x = 0, y is y = 20

When x = 10, y is y = 17

etc etc

Answer 24

So if a question says find the equation of the line we dont need x and y right

Answer 25

You don't want x and y fixed since they represent entities that should should/could change (namely time and water level)

Answer 26

no it doesn't make sense to find x and y to be honest when they ask something like that

Answer 27

Thanks @jim_thompson5910

Answer 28

yw