HELP PLZ GUYS.! Use Descartes’ rile of signs to describe the roots for each polynomial function.

m(x) = x^3 + 3x^2 - 18x - 40

AND

w(x) = x^4 + 4x^3 - 7x^2 + 20x - 21

The price of a lawn mower is x dollars. the store is having a 75% end of summer clearance sale. which expression can be used to find the clearance price of the mower? a) .25x b) .75x c) x - .25(75) d) x + .25(75)