From the description given for the triangle above, I think the type of triangle that is represented would be a right triangle. This type of triangle contains a right angle and two acute angles. In order to say or prove that it is a right triangle, it should be able to satisfy the Pythagorean Theorem which relates the sides of the triangle. It is expressed as follows:
c^2 = a^2 + b^2
where c is the hypotenuse or the longest side and a, b are the two shorter sides.
To prove that the triangle is indeed a right triangle, we use the equation above.
c^2 = a^2 + b^2
c^2 = 20^2 = 10^2 + (10sqrt(3))^2
400 = 100 + (100(3))
400 = 400
Answer:
The answer is "40 nickels/standard coins"
Step-by-step explanation:
The ratio of 40 nickels/standard coins is constant, that is 1 roll with coins per 40 nickels, that's why the equation is y = 40 
RS+ST=RT
RS=7y-4
ST=y+5 using RS and RT in the first equation gives you:
7y-4+y+5=RT combine like terms on left side
8y+1=RT, and we are told that RT=28 so:
8y+1=28 subtract 1 from both sides
8y=27 divide both sides by 8
y=27/8
(RS=19 5/8, ST=8 3/8, RT=28)
I got D for this one................
If you convert 1/4 into 5/20 then 13/20 + 5/20 = 18/20