Which Integer is halfway between +4 and -4

In trapezoid efgh, m∠hef=(4x2+16)∘ and m∠gfe=(5x2+12)∘. find the value of x so that efgh is isosceles.

Prove that 16^4-2^13-4^5 is divisible by 11.

The graph below shows the line of best fit for data collected on the number of cell phones and cell phone cases sold at a local electronics store on twelve different days. number of cell phone cases sold 50 * 0 5 10 15 20 25 30 35 40 45 number of cell phones sold which of the following is the equation for the line of best fit? a. y = 0.8x b. y = 0.2x c. y=0.5x d. y = 0.25x