<span>We can safely assume that 1212 is a misprint and the number of seats in a row exceeds the number of rows by 12.
Let r = # of rows and s = # of seats in a row.
Then, the total # of seats is T = r x s = r x ( r + 12), since s is 12 more than the # of rows.
Then
r x (r + 12) = 1564
or
r**2 + 12*r - 1564 = 0, which is a quadratic equation.
The general solution of a quadratic equation is:
x = (-b +or- square-root( b**2 - 4ac))/2a
In our case, a = 1, b = +12 and c = -1564, so
x = (-12 +or- square-root( 12*12 - 4*1*(-1564) ) ) / 2*1
= (-12 +or- square-root( 144 + 6256 ) ) / 2
= (-12 +or- square-root( 6400 ) ) / 2
= (-12 +or- 80) / 2
= 34 or - 46
We ignore -46 since negative rows are not possible, and have:
rows = 34
and
seats per row = 34 + 12 = 46
as a check 34 x 46 = 1564 = total seats</span>
We know the area of the middle rectangle is 48 (length * width). removing that rectangle leaves us with two semicircles. you can combine those semicircles to be the equivalent of one circle. the area for a circle is r^2 * pi. we know the diameter is 4 because that is where we cut the semicircles. radius is half the diameter, so r is 2. 2^2 is 4, 4* pi is 12.56. add 12.56 (area of semicircles) with 48 (area of rectangle) and we get 60.56
Answer:
I think it is D
Step-by-step explanation:
Answer:
its a combination problem, so in your calculator put 9 nCr 4 and you'll get 126. i hope this helps. :)
Step-by-step explanation:
You can use a calculator for this if you have the graphing kind (I use a Ti-84) and when plugging the equation in, the answers should be b, d, and e
