Precal question

Question

Kiran drove from Tortula to Cactus, a distance of 270 mi. She increased her speed by 20 mi/h for the 370 mi trip from Cactus to Dry Junction. If the total trip took 10 h, what was her speed from Tortula to Cactus?

Answer 1

Let x mi/h be her speed from Tortula to Cactus, so her speed is x+20 from Cactus to Dry Junction

time=distance/speed

270/x+370/(x+20)=10

simplify, you get x^2-44x-540=0

(x-54)(x+10)=0

x=54 or x=-10(not reasonable, delete)

her speed from Tortula to Cactus is 54mi/h