HELP MEE!! 50 points :)

Complete the square to rewrite the following equation. Identify the center and radius of the circle. You must show all work and calculations to receive credit.

x2 + 2x + y2 + 4y = 20

What are the measures of ∠a, ∠b, ∠c and ∠d? explain how to find each of the angle measure.

What term makes it inconsistent y=2x - 4

A33 gram sample of a substance that's used to detect explosives has a k-value of 0.1473. n = noekt no = initial mass (at time t = 0) n = mass at time t k = a positive constant that depends on the substance itself and on the units used to measure time t = time, in days