Question

PLZ HELP!!!

Determine the slope & y-intercept. Show your work.

Answer 1

For #3 the chart is basically as x in (x) and f(x) as in Y

The domain is the x

the range is the Y

Now we can do slope formula

y2-y1/ x2-x1

Pick two random points for example to make life easier here Ill do

(2,5) and (3,9)

Now plug it in

3-2=1

9-5=4

4/1

4 is the slope.

The Y intercept is consisted of

y=mx+b

Wheras y and x you just leave it alone while m is the slope and b is the y-intercept

Now in order to find the Y intercept we need the X to be 0.

So it has to be (0, y)

Now we already found out the slope which is 4/1

And the slope is also the rate of change. Using that information we can just add 4 to the y whilst adding 1 to the x.

Now we already have it set up for us.

We can start from (-1, -7)

So following the order

add 1 to x and 4 to y

(0, -3)

Now we know the y- intercept which is -3

Now plug it in all together

-3 is (b)

For number 4 you have a graph. This should be much less work. Its going on a negative slope so we already know the slope is gonna be negative. So theres 2 ways, we can go on a random point and then count the rise/ run Or we can find 2 points on the graph and then Do the slope formula. I’m gonna do the rise over run So I’m gonna start from a given point and its rise 1 and then run left since its a negative slope 5 times and it puts me to the second point.

The slope is 1/5

The y intercept, we just need to find (b) or the y intercept

So in this case where does the line first make contact with the Y axis in this case it’s on the point (0, -1)

the y intercept is -1

Answer 2

Notes:

y = mx + b

- m is the slope, or how steep it is

- b is the y-intercept, or where the line hits the y-axis

[3]

m = 4

b = -3

() For slope, we will do change in y divided by change in x

() 9 - - 11 / 3 - -2 -> 20 / 5 = 4

() We will take our equation with our slope from above, plug in a coordinate point, and then solve for b

() y = 4x + b -> 9 = 4(3) + b -> 9 = 12 + b -> -3

() So, when x is 0 the y will be -3

[4]

m = -1/5

b = -1

() For slope, since it is a graph, we can use rise over run (count how many up/down for the numerator, and then count how many left/right for the denominator)

() This results in -1/5, it is negative because the slope is going down from the top left to the bottom right

() The line hit's the y-axis at -1, so we can tell this is our b

Have a nice day!

I hope this is what you are looking for, but if not - comment! I will edit and update my answer accordingly. (ノ^∇^)

- Heather