Answer:
- 24
Step-by-step explanation:
I think?
hello im new
Answer:
Rate in still water = 45 km/h
Rate of the current = 10 km/h.
Step-by-step explanation:
Let the rate of the current be x and rate in still water be y.
So the rate of the boat upstream is y - x and the rate downstream = x + y.
Rate upstream = distance / time
y - x = 105/3 = 35 ...... (1)
Rate downstream:
y + x = 165/3 = 55 .......(2)
Adding (1) + (2):
2y = 90
y = 45 km/h.
Using equation (1):
45 - x = 35
x = 45-35 = 10 km/h.
Answer:
Step-by-step explanation:
3x2 - y2 = 9.........(1)
x2 + 2y2 = 38......(2)
Let x^2 = a and y^2 = b
:- the two equations becomes
3a - b = 9..........(3)
a + 2b = 38.......(4)
Multiplying (4) by 3
3a + 6b = 114........(5)
Substracting (3) from (5)
3a - 3a + 6b - (-b) = 114 - 9
6b +b = 105
7b = 105
b = 105/7
b = 15
And 3a - b = 9 putting b = 15
3a - 15 = 9
3a = 15+9
3a = 24
a = 24/3
a = 8
And
x^2 = a
x^2 = 8
x = √8
x = √(4×2)
x = 2√2
Also y^2 = b
y^2 = 15
y = √15
I do not think we need to rewrite the first two numbers in the given above because they are already the simplest forms of themselves being whole numbers. However, the third number may be rewritten as 1/2 by dividing both numerator and denominator by 5 and the last one as 2/25 by dividing both numerator and denominator by 4.