Answer:
15.

16. 10 ml of 20% saline and 40 ml of 10% saline
Step-by-step explanation:
A chemist takes x ml of 20% saline and y ml of 10% saline. In total, he takes
x + y ml that is 50 ml, so

There are
ml of salt in x ml of 20% saline and
ml of salt in 10% saline. There are
ml of salt in 50 ml of 12% saline. Thus,

15. We get the system of two equations:

16. Solve this system. From the first equation:

Substitute it into the second equation:

Answer:
D
Step-by-step explanation:
2/5 is a rational number and square root of 3 is irrational
The distance the ships traveled are like the legs of a triangle and the question wants to know the hypotenuse. To find the hypotenuse, use the pythagorean theorem. this is a^2 + b^2 = c^2, with a and b being the legs and c being the <span>hypotenuse.
</span>Plug in known values:
84^2 + 62^2 = c^2
Solve:
84^2 = 7056
62^2 = 3844
7056 + 3844 = c^2
7056 + 3844 = 10900
10900 = c^2
Now you just need to isolate c by finding the square root of both sides.
√10900 = 104.403
√c^2 = c
So c = 104.403, or just 104.40 when rounded to the nearest tenth.
And if c is 104.40, then that means the hypotenuse is 104.40.
And all of that basically means that the distance between the ships is 104.40 miles.
Answer:
B
Step-by-step explanation:
Using the cosine ratio in the right triangle and the exact value
cos45° =
, then
cos45° =
=
=
( cross- multiply )
c = 3
1. -1
2. 1
3. 5
4. -1
5.-1
6. -3