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Simplify 21.5 ÷ 5 - 1/5 of (20.5 - 5.5) + 5.5 x 8

Which value is not a solution of 8x^3 – 1 = 0

If 7x=9y, y/z = 7/5 , then x/z = (a) 2/7 (b) 7/9 (c) 9/5 (d) 9/7 (e) 5/9

What are the domain and range of the function below? a) domain: (-4,0) range: [-2,infinity) b) domain: (-3,0) range: [-2,infinity) c) domain: (-infinity, infinity) range: [-2, infinity) d) domain: [-2,infinity) range: (-infinity, infinity)