Question

Write an equation for the line...
will reward medal.

Answer 1

@noseboy908

Answer 2

To start off, what is slope-intercept form?

Answer 3

y = mx + b

Answer 4

Correct, so let's use that as a base. What are the two variables and what do they stand for in that equation?

Answer 5

m = slope
b = y intercept

Answer 6

Correct again. Now, looking at your graph what is the point on the y axis where the line intersects it?

Answer 7

-2, i think?

Answer 8

and -5 on the x axis, i believe.

Answer 9

Yep! But for our sake you need not worry about the x-intersect. Now knowing that b=-5, let's establish m. How do you find the slope?

Answer 10

you could divide x & y cooridnates, can't you?

Answer 11

no, no no.. divide the difference of the x & y cooridnates

Answer 12

You may be right, show your math here trying that out.

Answer 13

okay, no.. i'm stuck again.

Answer 14

if i do (-2, -6) then -2 - -6= 4

Answer 15

switch that around

Answer 16

it should be -6, -2
-6 - -2 =-4

Answer 17

I've never seen that method before, but it certainly does not apply here. Look at the graph with me, knowing that slope=rise/run.

Answer 18

Starting from any point that is clearly on one of the graph's line's intersections. Does the line go up or down (looking from left to right)?

Answer 19

the line's going down, right..? i'm not good at this stuff. none of it makes sense.

Answer 20

You're right! It goes down, so the slope will be negative. That tells us the rise will be negative. Next count how many lines you have to go down before you get to a horizontal line where you have another clear point of the graph (one that cleanly passes through the intersecting lines of the graph)

Answer 21

is that where the y intercept cuts in at -2?

Answer 22

That can be one starting point, yes. How many units down and how many units right do you have to go before hitting another clean point on the graph?