Paired Parabolas
What's the same and what's different about the following pairs of equations?
- $y=x^2-4$ and $y+x^2-4=0$
- $y=4-9x^2$ and $y+4=9x^2$
- $2y=4x^2-6$ and $-(y-3)=2x^2$
If you were given the following picture, could you suggest the equation of its pair?
How about if you were given this picture instead?
Could you give the equation of its pair?
Underground Mathematics is hosted by Cambridge Mathematics. The project was originally funded by a grant from the UK Department for Education to provide free web-based resources that support the teaching and learning of post-16 mathematics.
Visit the site at undergroundmathematics.org to find more resources, which also offer suggestions, solutions and teacher notes to help with their use in the classroom.
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