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:
Therefore the friends will have to buy 511 feet of fence (rounding up) or 510 feet of fence ( to the nearest foot).
Step-by-step explanation:
i) perimeter of rectangular yard = 319 feet
ii) perimeter of yard of friends 
iii) Therefore the friends will have to buy 511 feet of fence or 510 feet of fence ( to the nearest foot).
1/5 five being the denominator, because in math you must always simplify
Answer:
Anylize the results
Step-by-step explanation:
107° because a line is 180 degrees and 180 minus 73 is 107