Write as an expression and simplify: the square of the difference of x and 8y

x² - 16xy + 64y²

Step-by-step explanation:

The difference of x and 8y is x - 8y

The square of the difference is (x - 8y)² = (x - 8y)(x - 8y)

Expand by multiplying each term in the second factor by each term in the first factor, that is

x(x - 8y) - 8y(x - 8y) ← distribute both parenthesis

= x² - 8xy - 8xy + 64y² ← collect like terms

= x² - 16xy + 64y²

$4034.40

the perimeter of the field is the sum of the lengths of the four sides:

47 yd + 158 yd + 47 yd + 158 yd = 410 yd

the cost of 3 ft (1 yd) of fence is 3×$3.28 = $9.84.

so the cost of jake's wood perimeter fance is

(410 yd) × ($9.84 /yd) = $4034.40