F(n-1) = f(n) - 5, based off of the first one
Answer: Institutional Review Board
Answer:
86 milkshakes and 63 ice cream were sold
Step-by-step explanation:
Let the amount of milkshake sold be x
Let the amount of ice cream sold be y
If she sold 149 milkshakes and ice cream cones then;
x+y = 149 ... 1
If the milkshakes sold for $4 and the ice cream cones for $3, with total amount #533 collected then;
4x + 3y = 533 ....2
Solve both equations simultaneously
x+y = 149 ... 1 * 4
4x + 3y = 533 ....2 * 1
________________________
4x+4y = 596
4x+3y = 533
Subtract
4y-3y = 596-533
y = 63
since x +y = 149
x+63 = 149
x = 149 - 63
x = 86
Hence 86 milkshakes and 63 ice cream were sold
Answer:
The answer is D(20)
Step-by-step explanation:
I don't know the exact algebraic explanation, however, this is how I did it.

If you divide the second equation into seperate twos, you will get 2*2*2*2*2*2 = 
Therefore,
meaning that x is equal to 6. Now The next bit is trial and error, 20-6=14. 
Last thing to do is to add x+y=6+14. That is why the answer is 20.
If you wait a bit longer, someone will probably have a more algebraic explanation, however, you stated you only needed the answer so I hope this helped.
1 vinegar to 1/2 of oil is equivalent to 2 parts of vinegar to 1 part of oil
equation is y = 2x
the second option is the correct one.