Answer:
12
Step-by-step explanation: Ryan played 12 songs because 9+3=12
5x + y = 15
y = -5x + 15
Substituting y= -5x+15 from first equation into second equation:
3x + 2y = 16
3x + 2·(-5x + 15) = 16
3x - 10x + 30 = 16
-7x + 30 = 16
7x = 30 - 16 = 14
x = 2
Substituting x=2 into the first equation:
5x + y = 15
5(2) + y = 15
10 + y = 15
y = 15 - 10
y = 5
So your final answers are x=2 and y=5.
Any arithmetic sequence can be expressed as:
a(n)=a+d(n-1), a=initial term, d=common difference, n=term number
In this case a=5, and d=-2 so
a(n)=5-2(n-1) which can be simplified...
a(n)=5-2n+2
a(n)=7-2n
The domain is restricted to integers from 1 to +oo.
Roberta it would cost 52.80 for 22 wings
