If a circle has a diameter of 16 feet which expression gives it's area in square feet

Solve the equation 3x2 + 19x + 9 = 0 to the nearest tenth.

Astudent received the following grades last semester. find the student's semester grade point average. an a is algebra (3 credits), a b in history ( 3 credits), a in sociology ( 3 credits) a d in english ( 3credits) and a c in seminar ( 2credits). an a is worth 4 points, a b is worth 3 points a c is worth 2 points and a d is worth 1 point.

Can someone me do math because i am having a breakdown rn because i don’t get it