By buying two shirts, Charlie will save $10 x \( \frac{15}{100} \) = \( \frac{$10 x 15}{100} \) = \( \frac{$150}{100} \) = $1.50 on the second shirt.

So, his total cost will be
$10.00 + ($10.00 - $1.50)
$10.00 + $8.50
$18.50

A factorial has the form n! and is the product of the integer (n) and all the positive integers below it. For example, 5! = 5 x 4 x 3 x 2 x 1 = 120.

The equation for this sequence is:

a_n = a_n-1 + 3(n - 1)

where n is the term's order in the sequence, a_n is the value of the term, and a_n-1 is the value of the term before a_n. This makes the next number:

a₆ = a₅ + 3(6 - 1)
a₆ = 31 + 3(5)
a₆ = 46

Average speed in miles per hour is the number of miles traveled divided by the number of hours:

Solving for distance:

distance = \( \text{speed} \times \text{time} \)
distance = \( 45mph \times 6h \)
270 miles

First, solve for \( \left|x + 3\right| \):

\( \left|x + 3\right| \) + 1 = 0
\( \left|x + 3\right| \) = 0 - 1
\( \left|x + 3\right| \) = -1

The value inside the absolute value brackets can be either positive or negative so (x + 3) must equal - 1 or --1 for \( \left|x + 3\right| \) to equal -1:

So, x = -2 or x = -4.