If cosx cos(pi/7) + sinx sin(pi/7) = -(sqrt(2))/2, then x can (check all that apply) (will give medal & fan! ) a. pi/4 + pi/7 + 2npi b. 5pi/4 + pi/7 + 2npi c. 7pi/4 + pi/7 + 2npi d. 3pi/4 + pi/7 + 2npi

Acircular garden with radius of 8 feet is surrounded by a circular path with a width of 3 feet. what is the approximate area of the path alone? use 3.14 for π

The height of a flare fired from the deck of a ship in distress can be modeled by h(t)= -2(8t^2-52t-28), where h is the height of the flare above water and t is the time in seconds. a. find the time it takes the flare to hit the water.

[10 points, algebra 2]according to my answer key the restrictions are -1 and 4. but why not positive 1?