Composing functions means to use the output of the inner function as the input for the outer one. It gets really clear and simple if you explicitly write it out:
Now substitute 
:
Now, since 
, we know that 
gives as output twice the input. In this case, the input is , so the output will be twice as much:
Note that we also have
Answer:
Y = 40
Step-by-step explanation:
Change 1/2 to 2/4
2/4 y + 6 = 3/4y - 4
subtract 2/4y
6 = 1/4y -4
add 4
10 = 1/4y
multiply by 4 to get fraction to 1y or y
y = 40
Answer:
1,000,000
Step-by-step explanation:
1mm=1e-6km
10mm=1e-5km
100mm=1e-4km
1000mm=000.1km
10000mm=0.01km
100000mm=0.1km
500000mm=0.5km
1000000mm=1km
