group the 1st 2 terms and last 2 terms:
(Z63 -2z^2) + (9z-18)
factor out GCF:
z^2(z-2) + 9(z-2)
now factor the polynomial:
(z-2) (z^2+9)
7 yrds/sec because in the course of two seconds, he runs 14 yrds divide that by 2 to get 7 yrds/sec. you can allo chech with the next time which is 3 seconds more and he goes 21 yards more.
The answer is 3.50
Because 15-7 equal 8,6 times 0.75 equal 4.50, and 8-4.5 equal 3.50
