Length=(x+3)
Breadth=(x-3)
Height=(2x-5)
Answer: the speed of the boat on the lake is 9 mph
Step-by-step explanation:
Let x represent the speed of the boat on the lake or in still water.
The speed of the current in a river is 6 mph. This means that if the boat goes upstream against the speed of the current, its total speed would be (x - 6)mph. If the boat goes downstream against the speed of the current, its total speed would be (x + 6)mph.
Time = distance/ speed
Every day, his route takes him 22.5 miles each way against the current and back to his dock, and he needs to make this trip in a total of 9 hours. This means that the time taken to travel upstream is
22.5/(x - 6). The time taken to travel downstream is
22.5/(x + 6)
Since the total time is 9 hours, it means that
22.5/(x - 6) = 22.5/(x + 6)
Cross multiplying, it becomes
22.5(x + 6) + 22.5(x - 6) = 9
Multiplying through by (x + 6)(x - 6), it becomes
22.5(x - 6) + 22.5(x + 6) = 9[(x + 6)(x - 6)]
22.5x - 135 + 22.5x + 135 = 9(x² - 6x + 6x - 36)
22.5x + 22.5x = 9x² - 324
9x² - 45x - 324 = 0
Dividing through by 9, it becomes
x² - 5x - 36 = 0
x² + 4x - 9x - 36 = 0
x(x + 4) - 9(x + 4) = 0
x - 9 = 0 or x + 4 = 0
x = 9 or x = - 4
Since the speed cannot be negative, then x = 9
Answer:
30000+200000
Step-by-step explanation:15% bc its 3 years, 15% of 200000 is 30000
Complete question :
Jenna’s method: Mia’s method: 5(30 + 4) 5(30 + 4) (5)(30) + (5)(4) 5(34) = 170 150 + 20 = 170 Explain why both Jenna and Mia arrived at the same answer and the advantage of one method over the other.
Answer:
Kindly check explanation
Step-by-step explanation:
Jenna's method :
5(30 + 4) = 5(34) = 170
Mia’s method :
5(30 + 4) :
5(30) + 5(4)
150 + 20
= 170
With both methods, we will arrive at the same answer as justified in the workings above. However, Jenna's method gives a very simple approach and less complicated arithmetic by using the distributive property to overrode some multiplication process which Mia went through in her own calculation. Therefore, Jenna's method is less complicated and requires two simple steps at obtaining the final result.
