Word Problem Five On a 570 mile trip Andy averaged 5 mph fa

Word Problem Five - On a 570 mile trip, Andy averaged 5 mph faster for the last
240 miles than he did for the first 330 miles. The entire trip took 10 hours.
How fast did he travel for the first 330 miles?

Solution

D=RT or T=D/R
10=330/X+240/(X+5)
10=(330*(X+5)+240X)/X(X+5)
10=(330X+1,650+240X)/(X^2+5X)
10(X^2+5X)=570X+1,650
10X^2+50X-570X-1,650=0
10X^2-520X-1,650=0
10(X^2-52X-165)=0
10(X-55)(X+3)=0
X-55=0
X=55 MPH FOR THE 330 MILE TRIP.
55+5=60 MPH FOR THE 240 MILE TRIP.
PROOF:
10=330/55+240/60
10=6+4
10=10