Which expression is equivalent to -3.2(2x-2.1)?

a. -6.4x + 6.72
b. -6.4x - 6.72
c. 6.4x + 6.72
d. -6.4x + 2.1

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What is the axis of symmetry of the function f(x)=-(x+ 9)(x-21)

Secant be and cf intersect at point d inside a what is the measure of cde

Which statement is true about the extreme value of the given quadratic equation? a. the equation has a maximum value with a y-coordinate of -21. b. the equation has a maximum value with a y-coordinate of -27. c. the equation has a minimum value with a y-coordinate of -21. d. the equation has a minimum value with a y-coordinate of -27.