Answer:
4/6 or 66.67 percent
Step-by-step explanation:
Answer: 1/3
<u>Step-by-step explanation:</u>
When adding or subtracting fractions, they must have the same denominator.
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
Answer:
a = 1 and b = - 10
Step-by-step explanation:
Expand the right side of the identity
x(ax² - 3x + b) - 3(ax² - 3x + b)
= ax³ - 3x² + bx - 3ax² + 9x - 3b
= ax³ - x²(3 + 3a) + x(b + 9) - 3b
Equate the coefficients of like terms on both sides of the identity
x³ terms → ax³ with x³ ⇒ a = 1
x terms → - x with (b + 9)x ⇒ b + 9 = - 1 ⇒ b = - 10
It's transilation (if that's how you spell it)
