SOLUTION: In California, the distance from Jackson to Lodi is about 40 mi, as is the distance from Lodi to Manteca. Rico drove from Jackson to Lodi during the rush hour, stopped in Lodi for
Question 199315This question is from textbook Itermediate Algebra
: In California, the distance from Jackson to Lodi is about 40 mi, as is the distance from Lodi to Manteca. Rico drove from Jackson to Lodi during the rush hour, stopped in Lodi for a root beer, and then drove on to Manteca at 10 mph faster. Driving time for the entire trip was 88 min. Find his speed from Jackson to Lodi This question is from textbook Itermediate Algebra
You can put this solution on YOUR website! the distance from Jackson to Lodi is about 40 mi, as is the distance from Lodi to Manteca.
Rico drove from Jackson to Lodi during the rush hour, stopped in Lodi for a root beer, and then drove on to Manteca at 10 mph faster.
Driving time for the entire trip was 88 min. Find his speed from Jackson to Lodi
:
Let s = speed from J to L
then
(s+10) = speed from L to M
:
Distances for both legs of the trip given as 40 mi
:
Write time equation; Time = dist/speed; change 88 min to 88/60 = 22/15 hrs
;
J-L time + L-M time = 22/15 hrs + =
Multiply equation by 15s(s+10), results:
15(s+10)*40 + 15s(40) = 22s(s+10)
:
(15s+150)*40 + 600s = 22s^2 + 220s
:
600s + 6000 + 600s = 22s^2 + 220s
:
Arrange as a quadratic:
0 = 22s^2 + 220s - 1200s - 6000
:
22s^2 - 980s - 6000 = 0
Use the quadratic formula to find s
x = s; a=22; b=-980; c=-6000
:
You can do the math here
The positive solution should be; s = 50 is the speed from J to L
