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## Get ready for AP® Calculus

### Unit 2: Lesson 1

Intro to slope-intercept form

# Intro to slope-intercept form

Slope-intercept form (y=mx+b) of linear equations highlights the slope (m) and the y-intercept (b) of a line. Watch this video to learn more about it and see some examples.

## Want to join the conversation?

• My teacher actually said something about "rise over run." Could you talk little bit more about it?
• rise/run is basically another term name for y/x because for the "y" axis it rises or goes up vertically and the "x" axis runs or goes across horizontaly.
• What is the difference between y=mx+c and y=mx+b?
• The equation for slope-intercept for varies by your country.

In the US, Australia, Canada, Eritrea, Iran, Mexico, Portugal, Philippines and Saudi Arabia the notation is:
y = mx + b
In the UK, Australia (also), Bahamas, Bangladesh, Belgium, Brunei, Bulgaria, Cyprus, Egypt, Germany, Ghana, India, Indonesia, Ireland, Jamaica, Kenya, Kuwait, Malaysia, Malawi, Malta, Nepal, New Zealand, Nigeria, Oman, Pakistan, Peru, Singapore, Solomon Islands, South Africa, Sri Lanka, Turkey, UAE, Zambia and Zimbabwe
y = mx + c
In Afghanistan, Albania, Algeria, Brazil, China, Czech Republic, Denmark, Ethiopia, France, Lebanon, Netherlands, Kosovo, Kyrgyzstan, Norway, Poland, Romania, South Korea, Surinam, Spain, Tunisia and Vietnam: y = ax + b
In Azerbaijan, China, Finland, Russia and Ukraine:
y = kx + b
In Greece:
*ψ = αχ + β*
In Italy:
y = mx + q
In Japan:
y = mx + d
In Cuba and Israel:
y = mx + n
In Romania:
y = gA + C
In Latvia and Sweden:
y = kx + m
In Serbia and Slovenia:
y = kx + n
Let me know is I missed any!
• what is the easiest way to memorize this concept?
• Slope is basically just rise/run or Y change over X change. If it is a positive line, you will have a positive slope. If the line is negative, you will have a negative slope.
• When I think about slope I only think about "rise over run."
• Well when Sal talks about the slope as 'm' he means that m = rise/run, so you're right!
• I'm confused, by how did he got (y - 5) = 2 (x - 1) also can somebody reply quick because I'm just stuck right now
• I think its like solving variables on both sides?
• Also, what does B in mx+b stand for?
• B is the y-intercept of the line. It indicates point of intersection between the y-axis and the line.
• okay, so I understand this, but I always get lost when I start to plot my graph. Is there a specific number that you have to start with?
• You always start at the y intercept b. Either go up (if positive), down (if negative) or stay at (0,0) if there is no constant b.
• How many different way can you write an equation?
• an infinite number of ways. let's just look at y=x you could write it as y=1*x or y=1*1*x and so on with multiplying 1 multiple times. You could also do y = x + 1 - 1 or y = 2x / 2 or y = 10x * .1. Then you can combine these methods or use different numbers, like y = x + 2 - 2
• How is slope algrabra i dont understand