Find the perimeter of a square with sides of 6x+5

Prove that quadrilateral is a rhombus.

Noel is hoping to make a profit (in $) on the school play and has determined the function describing the profit to be f(t) = 8t – 2654, where t is the number of tickets sold. what does the number 8 tell you?

Find the condition that the zeros of the polynomial f(x) = x^3+3px^2+3px+r may be in a.p.