PLEASE HELP ME ITS WORTH 25 pts (question number 29)

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A, C, D

Step-by-step explanation:

In a proportional relationship, y = kx, k is the constant of proportionality.

A)

4y = x

y = 1/4 x

k = 1/4      Yes

B)

y = 4x

k = 4      No

C)

32y = 8x

y = 8/32 x

y = 1/4 x

k = 1/4    Yes

D)

y = 0.25x

k = 0.25 = 1/4     Yes

E)

1/4 y = 2x

y = 4 * 2x

y = 8x

k = 8     No

A, C, D

you just switch the numbers basically so it would be 3/17

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