Answer:
<h2>The lengths of the bases of the trapezoid:</h2><h2>
42/h cm and 84/h cm.</h2>
Step-by-step explanation:
The formula of an area of a triangle:

<em>b</em><em> </em>- base
<em>h</em> - height
We have <em>b = 21cm, h = 6cm</em>.
Substitute:

The formula of an area of a trapezoid:

<em>b₁, b₂</em> - bases
<em>h</em><em> - </em>height
We have <em>b₁ = 2b₂</em>, therefore <em>b₁ + b₂ = 2b₂ + b₂ = 3b₂</em>.
The area of a triangle and the area of a trapezoid are the same.
Therefore
<em>multiply both sides by 2</em>
<em>divide both sides by 3</em>
<em>divide both sides by h</em>


Answer:
(B)
Step-by-step explanation:
Volume of fluid in the tank =1000 gallons
Initial Amount of Salt in the tank, A(0)= 30 pounds
Incoming brine solution of concentration 2 pounds of salt per gallon is pumped in at a rate of 4 gallons per minute.
Rate In=(concentration of salt in inflow)(input rate of brine)

The resulting mixture is pumped out at the same rate, therefore:
Rate Out =(concentration of salt in outflow)(output rate of brine)

Therefore:
The rate of change of amount of salt in the tank,

If B is the midpoint of AC, then AB=BC. It is also BC=AC-AB
AB = x + 6
AC = 5x - 6
BC = (5x - 6) - (x + 6)
We can kinda use distributive property, like this:
BC = 5x - 6 -x - 6
Combine like terms:
BC = 4x - 12
To verify, we can add AB and BC to see if their sum is equal to AC.
(x + 6) + (4x - 12) = 5x - 6
If we are correct, this equation will be true.
x + 6 + 4x - 12 = 5x - 6
Combine like terms:
6 + 5x - 12 = 5x - 6
5x - 6 = 5x - 6
It's correct!
BC = 4x - 12. Final Answer.
Let me know if you have any questions about this! :)
Answer:
4 & 17/20
Step-by-step explanation:
Answer:
1
Step-by-step explanation:
You will be multiplying 1 into 2. You then subtract 1 from 2.
which will give you 1= x