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:

8y⁷ - 9y⁷
(8 - 9)y⁷
-y⁷

To find the average of these 4 numbers add them together then divide by 4:

\( \frac{14 + 8 + 14 + 8}{4} \) = \( \frac{44}{4} \) = 11

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 have in common.

The distributive property for multiplication helps in solving expressions like a(b + c). It specifies that the result of multiplying one number by the sum or difference of two numbers can be obtained by multiplying each number individually and then totaling the results: a(b + c) = ab + ac. For example, 4(10-5) = (4 x 10) - (4 x 5) = 40 - 20 = 20.

To subtract these radicals together their radicands must be the same:

4\( \sqrt{12} \) - 4\( \sqrt{3} \)
4\( \sqrt{4 \times 3} \) - 4\( \sqrt{3} \)
4\( \sqrt{2^2 \times 3} \) - 4\( \sqrt{3} \)
(4)(2)\( \sqrt{3} \) - 4\( \sqrt{3} \)
8\( \sqrt{3} \) - 4\( \sqrt{3} \)

Now that the radicands are identical, you can subtract them: