The factors of a number are all positive integers that divide evenly into the number. The factors of 36 are 1, 2, 3, 4, 6, 9, 12, 18, 36.

First, solve for \( \left|a + 4\right| \):

\( \left|a + 4\right| \) + 1 = 3
\( \left|a + 4\right| \) = 3 - 1
\( \left|a + 4\right| \) = 2

The value inside the absolute value brackets can be either positive or negative so (a + 4) must equal + 2 or -2 for \( \left|a + 4\right| \) to equal 2:

So, a = -6 or a = -2.

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

Solving for time:

time = \( \frac{\text{distance}}{\text{speed}} \)
time = \( \frac{45mi}{45mph} \)
1 hour

To add these fractions, first find the lowest common multiple of their denominators. The first few multiples of 4 are [4, 8, 12, 16, 20, 24, 28, 32, 36, 40] and the first few multiples of 10 are [10, 20, 30, 40, 50, 60, 70, 80, 90]. The first few multiples they share are [20, 40, 60, 80] making 20 the smallest multiple 4 and 10 share.

Next, convert the fractions so each denominator equals the lowest common multiple:

\( \frac{8 x 5}{4 x 5} \) + \( \frac{4 x 2}{10 x 2} \)

\( \frac{40}{20} \) + \( \frac{8}{20} \)

Now, because the fractions share a common denominator, you can add them:

\( \frac{40 + 8}{20} \) = \( \frac{48}{20} \) = 2\(\frac{2}{5}\)

Use PEMDAS (Parentheses, Exponents, Multipy/Divide, Add/Subtract):

4 + (5 + 4) ÷ 2 x 5 - 3²
P: 4 + (9) ÷ 2 x 5 - 3²
E: 4 + 9 ÷ 2 x 5 - 9
MD: 4 + \( \frac{9}{2} \) x 5 - 9
MD: 4 + \( \frac{45}{2} \) - 9
AS: \( \frac{8}{2} \) + \( \frac{45}{2} \) - 9
AS: \( \frac{53}{2} \) - 9
AS: \( \frac{53 - 18}{2} \)
\( \frac{35}{2} \)
17\(\frac{1}{2}\)