Find the x intercepts of y=2x^2+x-21

Ineed to learn how to solve this problem

The dolphins at the webster are fed 1/2 of a bucket of fish each day the sea otters are fed 1/2 as much fish as the dolphins how many buckets of fish are the sea fed each day? simplify you answer and write it as a proper fraction or as a whole or mixed number

Kai walked one and two-thirds of a mile on saturday and four and one-sixth of a mile on sunday. how many miles did kai walk?