Graphing Lines in Slope-Intercept Form (y = mx + b)

The equations for lines come in different forms, and slope-intercept form is the classic! It's got everything you need right there, a slope, a y-intercept, what more could you ask for? Let's learn how to find the equation of a line in this form given two points on the line.

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[aminmkyt]

Hey just wanted to congratulate you for getting 2k subs in 6 hours, wish you a pewdiepie shout out

[ram]

I have a question, why is the slope in the first one 2, we have the points (-6, -3) and (0, 9), I calculated the slope which is 9-(-3)/0-6 which gives 12/-6 which is -2. I can't figure it out if I did something wrong or if the exercise is wrong.

[thegoodlydragon]

Sorry to bother you Dave, I'll bet you're pretty busy now. But would you mind explaining briefly when you changed 5 into 15/3 in the example? How does that help? How do I know what fraction to change the y term into in any given equation?

[antonioalmaraz]

When is your next video? It is these types of videos that remind me that the internet isn't all that cruel and not everybody stabs you in the back while reciting the whole declaration of independence.

[thqsfr]

While me who still doesn't understand anything because I suck at math.

[SsempijjaNawufaruh]

Comprehension is wrong
When I used (-6, -3) I got y=2x-15
When I used (0, 9) I got y=2x+9

[ReimskyToussaint]

Isn't the y-intercept also considered (alternatively) as the actual point where the line intersects the y-axis (in this case, not just the y-coordinate) and can this be expressed as an ordered pair (0, y)?

Thanks for your videos. Respect.

[vinukmethsha]

thank you very much for the maths series you are a god to me

[twrxzq]

how do we figure out which one is point 1 and point 2? coz it gives different solutions😢

i got the #1 right but for #2 i got y=-2x+3 since i used 7-5 / -2-(1) = -2 as my slope and not 5-7 / 1-(-2) = -2/3😢

[MiltosPol-qnzh]

When are you going to start geometry???

[abdikarinyusuf]

Daved can you speak slowly when you make expanig math graphbg ir slop than

[lizzlefizzleforizzle]

Hold up wait a minute. At the beginning (-2, 3) and (1, 5) points… I understand 5-3=2. But how is 1 -(-2)= to 3? Shouldn’t it be -1? This confuses the heck out of me because sometimes in math, it turns to a positive ie. -(-2) other times it will stay as a negative. Can someone please explain what and where the difference is?

[StacksWilson]

anyone else having to watch this for school?

[AfafAl-Meslmani]

i will never understand math. it needs to go to a therapist to solve its own problems i already have problems to solve.😩

[markreyronolo]

In checking comprehension, the first one. Isn't it y = -x + 9? Because 9-3/0-6 = 6/-6 = -1?

[Its_TRISHA-]

Can somebody please give me more practice problems

[sajayouussef]

I can't understand anything 😭😭😭😭😭

[GodbornNoven]

You can also use a system of equations to solve for the slope and the y intercept if you have two points that constitute a line.
say you have the points (2;-1) and (0;3)
This gives us:
-1=2m+b
3=0m+b
Here by doing this is kinda like assuming these two have the same equation, which is how you can calculate the equation of a line by just having the position of two of its points.