Answer: her speed on the bicycle is 8 mph
Step-by-step explanation:
Let x represent the speed at which she walks. If she rides 6 mph faster than she can walk, then the speed at which she rides is (x + 6) mph
Distance = speed × time
Eli walk from her house to a friends house in one hour. This means that the distance covered is 1 × x = x miles.
Distance on her bicycle in 15 minutes. Converting 15 minutes to hours, it becomes 15/60 = 0.25 hour. Distance covered while riding is 0.25(x + 6) = 0.25x + 1.5
Since the distance is the same,then
x = 0.25x + 1.5
x - 0.25x = 1.5
0.75x = 1.5
x = 1.5/0.75
x = 2
her speed on the bicycle is
x + 6 = 2 + 6 = 8 mph
Combine like terms (2x-3x=-x) then you're left with -x+6=5x-9. Get the X's on one side and the numbers on one side (-x+x=0, 5x+x=6x) (-9+9=0, 6+9=15) then you're left with 6x=15. Simplify and you have your answer