Answer:
C: 12.5
Step-by-step explanation:
The sides x and 11 could be defined as the Adjacent angle and the Hypotenuse. This means that we will use the cos function to solve this.
First we can set up our equation

Next we can solve for x by multiplying by x and dividing by 

Answer:
Step-by-step explanation:
try the numbers -3 -2 1 and 3
Since
are in arithmetic progression,




and since
are in geometric progression,




Recall that


It follows that

so the left side is

Also recall that

so that the right side is

Solve for
.

Now, the numerator increases more slowly than the denominator, since


and for
,

This means we only need to check if the claim is true for any
.
doesn't work, since that makes
.
If
, then

If
, then

If
, then

There is only one value for which the claim is true,
.
The total travelled for the first five hours eould be 450 km and divided by three leaves 150 km per 1/5 of his journey. travelling at 75 km per hour, it would take 4 hours to get through the remaining 300 km for him trip leaving a total time of 9 hours of traveling