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## Algebra (all content)

### Course: Algebra (all content)>Unit 9

Lesson 1: Parabolas intro

# Parabolas intro

Graphs of quadratic functions all have the same shape which we call "parabola." All parabolas have shared characteristics. For example, they are all symmetric about a line that passes through their vertex. This video covers this and other basic facts about parabolas.

## Want to join the conversation?

• does the parabolas ever "touch" and turn into an ellipse?
• I assume that you are talking about the lines of a parabola. If so, no. because then what you are looking at is not a parabola. It would be, as you said, an ellipse or circle.
• Does the opening upwards or opening downwards of a parabola depend on anything?
• What would the equation be for a Parabola that is sideways?
• x=y^2 would create a parabola that goes sideways. Note: it would not be a function.
• After a month, finally got to unit 14 🥹
• Why are they called "quadratics"?
• The Latin word for square is quadratum. Since the area of a square is the square of its side length, words similar to this are sometimes used to mean square, the operation. Quadratics are named thus because the function involves squaring the input.
• I dunno, parabolas seem to be a bit more curved than very straight forward...
• Can a parabola be sideways?
• Yes. If a parabola is sideways, x is equal to y^2, instead of the other way around. Note that a sideways parabola isn't a function, though.
• Is it possible to determine the magnitude of the curve of a parabola ?
Like line graphs have slopes which shows the magnitude of their slope-iness (i can't think of a better word :P ). So is there anything like that for parabolas ? And how do you find it ?