The commutative property states that, when adding or multiplying numbers, the order in which they're added or multiplied does not matter. For example, 3 + 4 and 4 + 3 give the same result, as do 3 x 4 and 4 x 3.

If the tiger has consumed 80 pounds of food in 8 days that's \( \frac{80}{8} \) = 10 pounds of food per day. The tiger needs to consume 130 - 80 = 50 more pounds of food to reach 130 pounds total. At 10 pounds of food per day that's \( \frac{50}{10} \) = 5 more days.

To fill a 15 gallon tank exactly halfway you'll need 7\(\frac{1}{2}\) gallons of fuel. Each fuel can holds 2\(\frac{1}{2}\) gallons so:

cans = \( \frac{7\frac{1}{2} \text{ gallons}}{2\frac{1}{2} \text{ gallons}} \) = 3

To subtract these fractions, first find the lowest common multiple of their denominators. The first few multiples of 8 are [8, 16, 24, 32, 40, 48, 56, 64, 72, 80] and the first few multiples of 16 are [16, 32, 48, 64, 80, 96]. The first few multiples they share are [16, 32, 48, 64, 80] making 16 the smallest multiple 8 and 16 share.

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

\( \frac{6 x 2}{8 x 2} \) - \( \frac{9 x 1}{16 x 1} \)

\( \frac{12}{16} \) - \( \frac{9}{16} \)

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

\( \frac{12 - 9}{16} \) = \( \frac{3}{16} \) = \(\frac{3}{16}\)

To add or subtract terms with exponents, both the base and the exponent must be the same. In this case they are so subtract the coefficients and retain the base and exponent:

6b⁴ - 7b⁴
(6 - 7)b⁴
-b⁴