Quadratic equations

What this lesson shows

x² minus 5x plus 6 equals zero. You could guess numbers all day… or you could draw one picture.

Try it yourself

Real questions from this lesson's worksheets — answers below each one.

1. Which function crosses the x-axis at x = 1 and x = −2?
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   (x − 1)(x + 2)
2. f(x) = (x − 1)(x + 2) crosses the x-axis at x = 1 and x = ?
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   -2
3. Find the y-intercept of f(x) = 2x² - 5x + 1. Give the y-value.
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   1
4. Which function crosses the x-axis at x = 2 and x = −1?
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   (x − 2)(x + 1)