Similar triangles to prove that the slope is constant for a line | Algebra I | Khan Academy

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Algebra I on Khan Academy: Algebra is the language through which we describe patterns. Think of it as a shorthand, of sorts. As opposed to having to do something over and over again, algebra gives you a simple way to express that repetitive process. It's also seen as a "gatekeeper" subject. Once you achieve an understanding of algebra, the higher-level math subjects become accessible to you. Without it, it's impossible to move forward. It's used by people with lots of different jobs, like carpentry, engineering, and fashion design. In these tutorials, we'll cover a lot of ground. Some of the topics include linear equations, linear inequalities, linear functions, systems of equations, factoring expressions, quadratic expressions, exponents, functions, and ratios.

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[Astro_]

You have single handedly saved my math grade. And for that, I thank you

[zombiesandvich]

Oh? you're reading the comments? instead of watching the video you're actually reading the comments?

[graceyant]

you're angel, i didn't understand anything about slopes until i watched this. thank you!

[lanog]

Very cool! I've never exactly tried to prove this.

[marianeescobar]

5 years ago this guy helped me with math fast forward to the present he’s STILL able to help me, that’s crazy🤯

[brooklynn]

Thank you this helped me so much I don’t understand algebra easily but you explained it really well thank you

[yusufjavadi]

I just had a question on how you know where to put the points can u please make a video on that

[portal_fan_]

wow 9 years later and still helping people out

[ig]

I had a question that why we can not draw the triangle on the other side of the line and I if we can how can we know which side to pick because different sides and starting points will give different things for example: if I get the slope of 3/-2 by drawing the triangle from the bottom side of the line like the one in this video and if I change the side and draw the triangle from the other side of the line it gives me 3/2, Which is positive and the other one is negative.

[prestonrichardson]

So why does this sound like a broken record