Cuatro personas invirtieron en su negocio cantidades proporcionales a 11, 15, 18 y

25. Si el que aportó más aportó 2800 soles más que el que aportó menos. ¿Cuánto

aportaron los cuatro?

a) 20 700

b) 13 800

C) 15 800

d) 11 800

e) 17 700

answer: 177/8

step-by-step explanation:

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step-by-step explanation:

answer: what are the following choices

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