16. Charles Benton's gross weekly salary is $421. His weekly federal withholding is $51.18. The Social Security tax is 6.2 percent of the first $90,000. The Medicare tax is 1.45 percent of gross pay. The state tax is 1.5
percent of gross pay. Each week he pays $12.40 for medical insurance. What are Benton's total deductions?
a. $108.90
C $110.90
b. $102.10
d.
$138.09
Lo

x^2 + 81

we can factor this using difference of square binomials.

rewrite the equation:

x^2 - (-81)

factor:

(a^2 - b^2) = (√a^2 + √b^2)(√a^2 - √b^2)

(x^2 - (-81) = (x + √-81)(x - √-81)

we can remove the - from under the radical by multiplying it by i.

(x^2 - (-81) = (x + i√81)(x - i√81)

(x^2 - (-81) = (x + 9i)(x - 9i)

we can check our answer by using foil:

x^2 - 9ix + 9ix - 81i^2

x^2 - 81^2

i^2 = -1

x^2 + 81