It would take 6
hours or 6.25 hours if John uses the 100 watt pump.
Answer:
Step-by-step explanation:
If it is, the first and last terms are perfect squares, and the middle term is twice the product of the roots of those squares.
16x^ = (4x)^2 . . . . a perfect square
49 = 7^2 . . . . . . . a perfect square
-2(4x)(7) = -56x . . . . . matches the middle term, so the factoring is ...
16x^2 -56x +49 = (4x -7)^2
_____
The sign in the binomial factors is the same as the sign of the middle term of the trinomial.
Answer:
Negative
Step-by-step explanation:
It's negative because my math teacher said so a few years ago. Sorry for the not so great explanation... I didn't pay attention that day.
10 L of 30 % saline solution can be formed by mixing 4 L of 60 % saline solution and 6 L of 10 % saline solution.
Step-by-step explanation:
Let x be the number of liters of 60% saline solution
Now we require 10 L of 30% saline solution.
Liter soln % liters saline %
30 % 10 0.3
60 % x 0.6
10 % 10-x 0.1
Now forming the algebraic equation,
0.6x + 0.1 (10-x) = 10 (0.3)
0.6x + 1 - 0.1 x = 3
0.5 x = 2
x = 4 ( 4 l of 60 % solution is required. So 10 % saline solution required is 10 - 4 = 6 L).
Hence, 10 L of 30 % saline solution can be formed by mixing 4 L of 60 % saline solution and 6 L of 10 % saline solution.
