3x-4=-31
+4 +4
3x=27
X=9
Hope this helps
Answer:
The number of mosquitoes is maximum for 6.5 inches rainfall.
Step-by-step explanation:
The given function is
.... (1)
where, M(x) is number of mosquitoes in millions and x the June rainfall in inches.
We need to find the rainfall that produces the maximum number of mosquitoes.
Differential the above function with respect to x.
.... (2)
Equate first derivative equal to 0.



Differential function (2) with respect to x.

Double derivative is negative. So, the value of function is maximum at x=6.5.
Therefore, the number of mosquitoes is maximum for 6.5 inches rainfall.
Answer: (0,0),(0,4), and (5,0)
Step-by-step explanation:
It is easy to find lengths of horizontal and vertical segments and distances from (0,0) so always place one vertex at the origin and one or more sides on an axis.
This answer has an x intercept and y intercept.
Answer:
Step 2: 20x = 80 + 10x
Step-by-step explanation:
Step 1: 20x - 10 = 80 + 10x
Add 10 to each side
20x - 10+10 = 80+10 + 10x
20x = 90 + 10x
Step 2: 20x = 80 + 10x This has the first error
Step 3: 10x = 80
Step 4: x= 8
Answer:
B. 200 doses
Step-by-step explanation:
Given,
1 dose is required for 100 mg,
Since, 1 mg = 0.001 g,
⇒ 100 mg = 0.1 g
⇒ 1 dost is required for 0.1 g,
Thus, the ratio of doses and quantity ( in gram ) is 
Let x be the doses required for 20 grams,
So, the ratio of doses and quantity is 


Hence, 200 doses can be obtained from 20 grams of the drug.
Option 'B' is correct.