Question

Calculate the equation of the line between the points (-6, -1) and (2, -1)

Answer 1

What is the standard equation of a line? y=mx+b.

m is the slope, it is rise/run and b is the y-intercept.

Try drawing it out to see if this helps.

Answer 2

I tried yet I dont understand.

Answer 3

Well, what does your picture look like? How much do you rise and how much do you run to get from one point to the next?

Where on the y-axis is the line touching at x=0?

Answer 4

Some what above -1?

Answer 5

(-6, -1) and (2, -1)
First find the slope of the line:
y - y
over
x - x

Once you find the slope try putting it into point-slope form:
y - y1 = m(x - x1)

Answer 6

After that you can change it easily from point-slope to standard form.

Answer 7

Im completely lost.

Answer 8

Do you want to do it the way I mentioned above?
Step by step?

Answer 9

Yes please

Answer 10

Ok, so first lets find the slope:
The formula to find slope is the difference between the y points over the difference between the x points.

Answer 11

So the one furthest to the right is Y2? And X2?

Answer 12

Look at your given points: (-6, -1) and (2, -1)
y values: -1 and -1
x values: 2 and -6

Answer 13

Okay

Answer 14

So find the difference between the y-values: -1 - (-1)

Answer 15

Jeremiah, I know this might take 30 minutes, but really play around with a graph of y based on x being multiplied with numbers and being added to numbers. Then you'll understand why y=mx+b. What is the difference between the graphs y=2x and y=x? What is the difference between y=x+1 and y=x? If you spend the time to figure this out you will understand and maybe even be able to answer your own questions! =D

Answer 16

2

Answer 17

I agree with @Kainui when you put these points on a graph it is definately easier to spot out the equation:)

Check again: Try -1 + 1 (two - signs equal a +)

Answer 18

0

Answer 19

sorry i did that and I thoughh it said 1+1

Answer 20

Yes. And 2 + 6?

Answer 21

8

Answer 22

0/8

Answer 23

Exactly! You see how there is a 0 in the numerator. Remember rise/run: so the line doesn't rise. The slope is 0.

Answer 24

B is slope right or is it m?

Answer 25

The line is a horizontal line.
m = slope
b = y-intercept

Answer 26

So whats y and x?

Answer 27

Ok so now we have the slope and we can make the point-slope equation, This is quick and easy:)

Answer 28

Pick one of the two original points (-6, -1) or (2, -1)

Answer 29

Whats the Y intercept?

Answer 30

y-intercept is where the line crosses the y-axis.

But in order to get to standard form (y = mx + b) you should put an equation is point-slope form(y - y1 = m(x - x1)

So you pick one point. Lets go with (-6, -1). Now just substitute the values into the equation:
(-6, -1)
m= slope = 0
y - (-1) = 0(x - (-6))
y + 1 = 0(x + 6)

Answer 31

**The y1 and x1 are where you put in the values of x and y

Answer 32

so the final equation Im geussing would end up bein y=-8x-1?

Answer 33

no. Remember that the m in y = mx + b is the slope. And we found that the slope was 0.
But your y-inercept(b) is correct:)
Try simplifying this:
First you must distribute the 0 into the x and the 6...
y + 1 = 0(x + 6)
y + 1 = (0 * x) + (0 * 6)
Keep in mind that you can never elliminate the x; 0 * x would be 0x

Answer 34

so what would it be?

Answer 35

So it would be:
y + 1 = 0x

Now you just want to leave the y alone on one side so subtract the 1 from both sides of the equation:
y + 1 - 1 = 0x -1
y = 0x - 1

Final answer:
The equation of the line between the points (-6, -1) and (2, -1) would be:
\[y = 0x + 1\]

Answer 36

Thats not one of the choices though

Answer 37

What are your choices?

Sorry it took so long to explain:) It looks complicated at first but it gets a lot easier after you do it a lot.

Answer 38

a. y = -1
b. x = -1
c. y = -8x - 1
d. y = -x - 8

Answer 39

A) y = -1
Sorry I had forgotten that when a line is horizontal the answer is just y = and the y-intercept....
Whenever you want to check an equation i suggest you use this: https://www.desmos.com/calculator
Just put in the equation(doesn't matter the format) and it shows the line.

Out of curiosity, are you in FLVS?

Answer 40

Oh no Im in BYU

Answer 41

Oh ok:)
I was asking cuz I took Algebra in FLVS last semester; and this was pretty much what I came to ask at openstudy every day until I got the hang of it:D

Answer 42

Hope I helped, as confusing as it might have been...:)
And I hope you do well on your classes!