- #1

roxas

- 21

- 0

john followed this route at xkm/h

he came down a different route

the length of the route is 25km

his average speed coming down increase by 2km/h than his average speed going up

it took john 1.5 hours less to come down than to go up

write an equation in x and show it simplifies to

3x^2 + 16x - 80 = 0

i tried doing it, but i can't reduce it to this equation. can anyone help me

i basically did this

20/x - 1.5 = 25/x+2

it can't reduce to the above equation. please help me. thx