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:
2.20752 x 
Step-by-step explanation:
The first thing you have to do is to look for the number of seconds in one year. You have to multiply 365 days by 86,400 seconds.
- 365 days refer to the total number of days per year
- 86,400 seconds refer to the number of seconds per day
Let's solve.
- 365 x 86,400 = 31,536,000 or 3.1536 x

<em>Therefore, one year has 3.1536 x </em>
<em> seconds.</em>
Next, you have to know the number of seconds in 10 billion years.
- (3.1536 x
) x (1.0 x
) = 3.1536 x 
The last step is to multiply the number of seconds in 10 billion years to 7 million tons of mass per second.
- (3.1536 x
) x 7,000,000 = 2.20752 x 
144 cm3 is what i came up with!
$125.4 is the answer to #1
#2 im not sure how the 10% effects the problem. so i cant help you there
If they have the same charge
x+x+x+x+x+x+x=-42
7x=-42
x=-6
so to check our answer
-6-6-6-6-6-6-6=-42
-12-12-12-6=-42
-24-18=-42
-42=-42