Answer:
The answer is the second one
Step-by-step explanation:
Answer:
16/5
Step-by-step explanation:
Let m and j be the current ages of Matthew and Jenny, respectively.
Now, Matthew is 3 times as old as Jenny, so the variables are in the following relation:

In 7 years, both of them will be 7 years older, i.e. their ages will be m+7 and j+7, and Matthew will be twice as old:

Now, remembering that m=3j, we can rewrite the second equation as

So, Jenny is 7 and Matthew is 21 (he's 3 times older).
In fact, in 7 years, they will be 14 and 28, and Matthew will be twice as old.
Answer:
(x + 39) or x = -39
Step-by-step explanation:
Set f(x) to 0
0 = 5x + 195
5x = -195
x = -39
64% of the gas tank is full