Subtraction doesn't mix with mult. or div. Are you sure you've copied this problem down correctly?
"decrease an amount (x) by 19" would be x - 19 (NO multiplication here)
Answer:
h=12
Step-by-step explanation:
by cross multiplying we get 1h=12 or h=12 so h=12
We start at 62 Fahrenheit. And every hour we drop two degrees. We want to know how long it took for the temperature to drop to 40 Fahrenheit.
If one hour passed, then the temperature dropped two degrees.
If two hours passed, then the temperature dropped 4 degrees.
See the pattern? We can define this as 2h. Where h represents time in hours.
We subtract 2h from 62.
We can write this as a function. F(h) = 62 - 2h.
Where F is the temperature in Fahrenheit. And h is the hour(s).
Now that we have the formula, let's plug in the value 40 Fahrenheit to see how long it took for the temperature to drop to 40 degrees.
40 = 62 - 2h
Subtract 62 from each side
-22 = -2h
Divide both sides by 2
h = 11
So, it took 11 hours for the temperature to drop to 40 Fahrenheit.
Answer:
after sprouting it lived for 100 days
Step-by-step explanation: