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Compare quadratic functions


How many roots do the functions have in common?
f, left parenthesis, x, right parenthesis, equals, 2, x, squared, minus, 4, x, minus, 16
A coordinate plane. The x- and y-axes both scale by one. The graph is the function y equals g of x which is a parabola that opens up. The function has an x-intercept at negative two, zero, a y-intercept at zero, negative four, a minimum around one, negative four point five, and another x-intercept at four, zero.
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