How to calculate a square root without a calculator

(7) 3 roots, 1 real & rational, 2 imaginary, 1 zero. Review solving polynomials by factoring using the Zero Property. Have the students predict the number of roots of x4 – 16 = 0, solve it by factoring into (x + 2)(x – 2)(x2 + 4) = 0 and applying the Zero Property, then predict the number of zeros and end-behavior of the graph of y = x4 – 16. ................
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