Answer:
8x^2
Step-by-step explanation:
(2x)^2(3−1)
= 4x^2(2)
= 8x^2
We have 5% and 6.5% acetic acid solutions and we need 200 ml of 6% acetic acid.
Set up two equations:
f means 5% and s means 6.5%
A) f + s = 200
B) .05f + .065s = (.06 * 200)
Multiplying equation A by -.05
A) -.05f -.05s = -10
B) .05f + .065s = 12 then adding both equations:
.015s = 2
<span>
<span>
<span>
we need 133.33</span> ml of 6.5% acetic acid and
66.67 ml of 5% acetic acid solution.
</span> </span>
Source:
http://www.1728.org/mixture.htm
Answer:
He can watch 8 movies
Step-by-step explanation:
100-40.66=59.34
6.71 x 8 = 53.68
therefore the most amount of movies he can watch is 8
Answer:
Jessica lived 10 months in Spain and 8 months in Colombia.
Step-by-step explanation:
Let x be the months Jessica spent in Spain, and y the months she spent in Colombia:
1. x + y = 18
Using the information of words per month learned in each country, we can also write the equation:
2. 160 * x + 200 * y = 3200
So now we have a system of <u>two equations and two unknowns</u>.
First we <u>express y in terms of x, in the first equation</u>:
We <u>replace y in the second equation</u>:
- 160 * x + 200 * (18 - x) = 3200
And <u>solve for x</u>:
- 160x + 3600 - 200x = 3200
Finally we <u>use that value of x in the first equation and solve for y</u>:
Jessica lived 10 months in Spain and 8 months in Colombia.
