Which of the equations are true identities? \begin{aligned} \text{A. }&(y+6)(y-7)+42=y^2-y \text{B. }&(x+3)(x-8)=x^2-5x \end{aligned} A. B. (y+6)(y−7)+42=y 2 −y (x+3)(x−8)=x 2 −5x

50 ! pls ! 12.  building codes regulate the steepness of stairs. homes must have steps that are at least 13 inches wide for each 8 inches that they rise.

a. discuss how to find the slope of the stairs.
b. describe how changing the width or height affects the steepness of the stairs.

Amachine part consists of a half sphere and a cylinder, as shown in the figure. the total volume of the part is π cubic inches.

Find the amplitude of a sinusoidal function that models this temperature variation