Answer:
The answer is below
Step-by-step explanation:
a) The maximum capacity of he tank is 6 L and initially it contains 11 mg of salt dissolved in 3 L of water. Solution enters the tank at a rate of 3 L/hr, therefore in x hours, the amount of water that have entered the tank = 3x.
Solution also leaves the tank at a rate of 2L/hr, therefore in x hours, the amount of water that have left the tank = 2x
Hence the amount of water present in the tank at x hours is given as:
3 + 3x - 2x = 3 + x
The time taken to full the tank can be gotten from:
3 + x = 6
x = 6 - 3
x = 3 hr
b)
![\frac{dQ}{dx}=3-\frac{2Q}{3+x}\\ \\\frac{dQ}{dx}+\frac{2Q}{3+x}=3\\\\let\ u'=\frac{2u}{3+x}\\\\\frac{u'}{u}=\frac{2Q}{3+x}\\\\ln(u)=2ln(3+x)\\\\u=(3+x)^2\\\\(3+x)^2Q]'=3(3+x)^2\\\\(3+x)^2Q=(3+x)^3+c\\\\Q(0)=11\\\\(3+0)^2(11)=(3+0)^3+c\\\\x=72\\\\Q=x+3+\frac{72}{(x+3)^2}\\ \\Q(3)=3+3+\frac{72}{(3+3)^2}=8\ mg](https://tex.z-dn.net/?f=%5Cfrac%7BdQ%7D%7Bdx%7D%3D3-%5Cfrac%7B2Q%7D%7B3%2Bx%7D%5C%5C%20%20%5C%5C%5Cfrac%7BdQ%7D%7Bdx%7D%2B%5Cfrac%7B2Q%7D%7B3%2Bx%7D%3D3%5C%5C%5C%5Clet%5C%20u%27%3D%5Cfrac%7B2u%7D%7B3%2Bx%7D%5C%5C%5C%5C%5Cfrac%7Bu%27%7D%7Bu%7D%3D%5Cfrac%7B2Q%7D%7B3%2Bx%7D%5C%5C%5C%5Cln%28u%29%3D2ln%283%2Bx%29%5C%5C%5C%5Cu%3D%283%2Bx%29%5E2%5C%5C%5C%5C%283%2Bx%29%5E2Q%5D%27%3D3%283%2Bx%29%5E2%5C%5C%5C%5C%283%2Bx%29%5E2Q%3D%283%2Bx%29%5E3%2Bc%5C%5C%5C%5CQ%280%29%3D11%5C%5C%5C%5C%283%2B0%29%5E2%2811%29%3D%283%2B0%29%5E3%2Bc%5C%5C%5C%5Cx%3D72%5C%5C%5C%5CQ%3Dx%2B3%2B%5Cfrac%7B72%7D%7B%28x%2B3%29%5E2%7D%5C%5C%20%5C%5CQ%283%29%3D3%2B3%2B%5Cfrac%7B72%7D%7B%283%2B3%29%5E2%7D%3D8%5C%20mg)
8 mg/ 6 L = 4/3 mg/L
The equation in slope-intercept form to represent the relationship between hours worked (x) and earnings in dollars (y) is y = $5 + $15x.
An equation in slope intercept form is usually written as: y = mx + b
Where:
If I earn $15 per hour when I babysit, the amount I earn increases by $15 every hour. $15 is the slope of the equation. After 3 hours, the total amount I would earn is: $15 x 5 = $45.
In order to determine the intercept, subtract $45 from $50.
$50 - $45 = $5.
A similar question was solved here: brainly.com/question/15355500
<span>the correct equation is
- 4j² + 3j - 28 =0
ax² + bx + c,
a = -4, b=3 c =- 28.
The discriminent D = b² - 4.a.cD = 3² - 4(-4)(-28)D = -439
If D ≥ 0 there are either 2 roots or one double if = 0)if D< 0, there are no real roots (but 2 imaginary roots)Since D < 0, then there is no real roots
The answer there is no real roots</span>
Answer:
I'm pretty sure it is A
Step-by-step explanation:
Answer:
The width of the frame must be 12 inches (15in by 12in)
Step-by-step explanation:
Given
See attachment for painting and frame
Required
Determine the dimension of the frame
To do this, we make use of the following scale ratio.

For the painting,

For the frame,

Since she wants to maintain the same ratio; both scale must be the same.
i.e.

Express as fraction


Make w the subject


<em>The width of the frame must be 12 inches i.e. 15in by 12in frame</em>