Answer:
23
Step-by-step explanation:
Brackets go first, 5 (y) - 4 (x) = 1. Now, 3 x 1 = 3, you do this because of the 3 next to the brackets. Now add them together.
5x + 4y = 32 ⇒ 45x + 36y = 288
9x - 1y = 33 ⇒ <u>45x - 5y = 165</u>
<u>41y</u> = <u>123</u>
41 41
y = 3
5x + 4(3) = 32
5x + 12 = 32
<u> - 12 - 12</u>
<u>5x</u> = <u>20</u>
5 5
x = 4
(x, y) = (4, 3)
I think that this is a combination problem. From the given, the 8 students are taken 3 at a time. This can be solved through using the formula of combination which is C(n,r) = n!/(n-r)!r!. In this case, n is 8 while r is 3. Hence, upon substitution of the values, we have
C(8,3) = 8!/(8-3)!3!
C(8,3) = 56
There are 56 3-person teams that can be formed from the 8 students.