SOLUTION: Solve the problem. A man rode a bicycle for 12 miles and then hiked an additional 8 miles. The total time for the trip was 5 hours. If his rate when he was riding a bicycle was 10

Algebra ->  Polynomials-and-rational-expressions -> SOLUTION: Solve the problem. A man rode a bicycle for 12 miles and then hiked an additional 8 miles. The total time for the trip was 5 hours. If his rate when he was riding a bicycle was 10       Log On


   

Question 169320This question is from textbook Introductory Algebra
: Solve the problem. A man rode a bicycle for 12 miles and then hiked an additional 8 miles. The total time for the trip was 5 hours. If his rate when he was riding a bicycle was 10 miles per hour faster than his rate walking, what was each rate? This question is from textbook Introductory Algebra

Answer by checkley77(12844) About Me  (Show Source):
You can put this solution on YOUR website!
D=RT OR D/R=T
12/X+8/(X-10)=5
[12(X-10)+8X]/X(X-10)=5
[12X-120+8X]/(X^2-10X)=5
20X-120=5X^2-50X
5X^2-50X-20X+120=0
5X^2-70X+120=0
5(X^2-14X+24)=0
5(X-12)(X-2)=0
X-12=0
X=12 ANS. FOR THE BIKE SPEED.
12-10=2 ANS. FOR THE WALKING SPEED.
PROOF:
12/12+8/2=5
1+4=5
5=5