3 years ago

Multiply and simplify the following complex numbers: (1 + 2i) x (1 - 4i)

Mathematics

1 answer:

Ivanshal [37]3 years ago

6 0

Answer:

9-2i

Step-by-step explanation:

(1 + 2i) * (1 - 4i)

(1*1)-(1*4i)+(2i*1)-(2i)*(4i)

(1)-(4i)+(2i)-(8i^2)

i^2 = -1

1-4i+2i+8

1-2i+8

9-2i

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Convert 35 kilometers to miles

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Answer:

The answer would be 21.248 miles

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I mark brainliest! please help! which graph shows all the values that satisfy 2/9x+ 3> 4 5/9

disa [49]

Answer:

The first option

Step-by-step explanation:

2/9 x + 3 > 4 5/9

2/9x > 4 5/9 - 3

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Helpppp plzzz The frequency histogram shows the lengths of trails in a large park.

Rus_ich [418]

Answer:

13 trails

Step-by-step explanation:

The histogram shows following numbers of trails:

0 - 6 km long - 5 trails;
6 - 12 km long - 9 trails;
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30 - 36 km long - 1 trail;
36 - 42 km long - 3 trails.

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3 years ago

PLEASE HELP!!!! i need help on all of these but if you only have 1 answer that’s still great

hodyreva [135]

Answer:

n = -6

x = -7

n = 27

Step-by-step explanation:

Question 1

-3n - n + 12 = 36

First we get all the variables to one side using subtraction property of equality.

-3n - n + 12 (-12) = 36 (-12)

-4n = 24

divide by the coefficient of n to isolate the variable

-4n/-4 = 24/-4

n = -6

Question 2

-2x - 3x - 15 = 20

-5x - 15 = 20

-5x = 35

x = -7

Question 3

3 + n/9 = 6

Isolate the n variable

n/9 = 6 - 3

multiply by 9

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Agata [3.3K]

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3 years ago