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3 years ago

Simplify: (-1+4i)(-12-9i)

Mathematics

2 answers:

tia_tia [17]3 years ago

7 0

$(-1+4i)(-12-9i)=(-1)(-12)+(-1)(-9i)+(4i)(-12)+(4i)(-9i)$

$= 12+9i-48i+36=48-39i$

sergiy2304 [10]3 years ago

5 0

-1 (-12 - 9i) + 4i (-12 - 9i)

= 12 + 9i + -48i + 9i^2

= 9i^2 + 39i + 12

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<h3>Find the Circumference</h3>

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For a solution not in terms of π, first, multiply 14 by π.

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To make this easier to present, round to the hundredths place.

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The final answer, dependent on the value you are asked to provide, is:

${\boxed{\displaystyle \frac{14\pi}{5} \ \text{inches}}$

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