Which shows the algebraic representation of the phrase
"Twenty-eight plus the product of five and a number and its value when a = 4.27
A 28 - Sn when n = 4.2 the value is 7
B 28 +3n when n = 4.2 the value is 49
C 28-3n when n= 4.2 the value is 112.6
D 28+ Sn when n = 4.2 the value is 122.6

can you post the graph?

ωєℓℓ ωιтн тнαт ιиfσ

тнє вαѕє ιѕ 30

αи∂ тнє нєιgнтн ιѕ 30

нσρє ι ¢συℓ∂ нєℓρ

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