Answer:
11
Step-by-step explanation:
because the length of 12 is the same of t+1 so 11+1=12
youre welcome
Answer:
145
Step-by-step explanation:
Its the opposite angle of 145
395, 390, 398 those are the numbers
Answer:
$10
Step-by-step explanation:
Greg's amount of money = $11
26-11 = 15 =
Jan's amount of money = $10
William's amount of money = $5
5x2 = 10
Answer:
2 km/h
Step-by-step explanation:
Let x represent the speed of the river current, t₁ be the time spent rowing against the current and t₂ be the time spent rowing with the current.
Since the speed of the still water = 20 km/h.
The speed of rowing against the current = (20 - x)
The speed of rowing with the current = (20 + x)
We know that velocity = distance / time. Hence time = distance / velocity
t₁ = 36 / (20 - x)
t₂ = 22 / (20 + x)
but t₁ + t₂ = 3 hours
Therefore:
3 = 36 / (20 - x) + 22 / (20 + x)
multiply through by 400 - x²
3(400 - x²) = 36(20 + x) + 22(20 - x)
1200 - 3x² = 720 + 36x + 440 - 22x
3x² + 14x -40 = 0
This gives x = -6.7 or x = 2
x cannot be negative therefore x = 2 km/h
The speed of the river current is 2 km/h
