Answer:
I have no idea how to answer this... :P
<3
Sorry, I am quite a dummy.
Answer:

Step-by-step explanation:
we have


we know that

substitute the variable x in the function g(x) by the function f(x)
so

Evaluate 
For x=0


Make a proportion
81/30 = x/600
600/30 = 20
x/81 = 20
x = 1620
Solution: 1620 calories
Let q and n represent the number of quarters and nickels respectively.
q=3n and .05n+.25q=1.6 These are the conditions in mathematical terms.
To solve, use the value of q from the first equation in the second equation to get:
.05n+.25(3n)=1.6 carry out indicated multiplication on left side
.05n+.75n=1.6 combine like terms on left side
.8n=1.6 divide both sides by .8
n=2, since q=3n
q=6
So Peggy had 2 nickels and 6 quarters.
Answer:
9in
Step-by-step explanation:
54 = 1/2(12*x)
54 = 6*x
x = 9
Check
12 x 9 = 108
108/2 = 54