Write each of the equations below in standard form (i. e. y = ax^2+bx+c y=ax 2 +bx+c): a. y = 3(x-7)(x+4) y=3(x−7)(x+4) b. y = 2(x-3)^2 + 5 y=2(x−3) 2 +5 c. y = -2(x+3)(x+5) y=−2(x+3)(x+5) d. y = -3(x-4)^2 + 8y=−3(x−4) 2 +8

Parabolas y=−2x^2 and y=2x^2 +k intersect at points a and b that are in the third and the fourth quadrants respectively. find k if length of the segment ab is 5.

Three numbers x, y, and z are in the ratio 2: 7: 8. if 12 is subtracted from y, then three numbers form a geometric sequence (in the order x, y–12, z). find x, y, and z. there are 2 sets.

He ! a group of farmers planned to clean 80 acres of wheat per day to finish the work on schedule. right before the work started, they received a new piece of machinery that them clean 10 more acres per day than originally planned. as a result of increased productivity in the last day before the deadline they only had to clean 30 acres. how many acres of wheat did the group of farmers have to clean?