1answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
Arisa [49]
3 years ago
12

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
You might be interested in
An astronaut drops a rock into a crater on the moon. The distance, d(t), in meters, the rock travels after t seconds can be mode
jek_recluse [69]
Given:
d(t) = 0.8t²

d(5) = 0.8*5² = 0.8 * 25 = 20
d(10) = 0.8*10² = 0.8 * 100 = 80

Average speed = distance traveled / time of travel
Average speed = 20 meters / 5 seconds = 4 meters per second

Average speed = 80 meters / 10 seconds = 8 meters per second

4 mps + 8 mps = 12 mps 
12 mps / 2 = 6 mps the average speed in meters per second between 5 and 10 seconds. 
5 0
3 years ago
Find the distance around one-fifth of a circle with diameter of 14 inches
Step2247 [10]

To solve this problem, you will need to know the formula to find the circumference of a circle given the diameter of a circle. After calculating the circumference, you will then divide this result by 5 to obtain the final answer needed for this problem.

<h3>Find the Circumference</h3>

The circumference of a circle is found using the formula C = 2πr.

C = 2\pi r

We are given the diameter. The radius can be found using r = D/2.

\displaystyle r=\frac{D}{2}

\displaystyle r=\frac{14}{2}

r=7

Plug in the radius to the formula for a circle's circumference: C = 2πr.

C = 2 \pi (7)

Rearrange the equation to distribute the 7 into the 2π.

C = 7(2\pi)

Distribute the 7.

C=14\pi

<h3>Find One-Fifth of the Distance</h3>

To find one-fifth of the distance (formally termed the circumference) around the circle, divide the circumference by 5.

\displaystyle \frac{14\pi}{5}

If you are looking for a simplified answer in terms of π, this will suffice. If you need an exact answer that does not reference π, continue reading.

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

14\times\pi = 43.98229715

Divide this value by 5.

\displaystyle \frac{43.98229715}{5} = 8.7964594

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

8.7964594 \approx 8.80

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

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

\boxed{\text{approximately} \ 8.8 \ \text{inches}}

6 0
2 years ago
MATH HELP
sergeinik [125]

Answer:

rate=1.28571428571.. (1.29) miles per minute, or 77.1428571429.. (77.14) mph

Step-by-step explanation:

<em>"use distance = rate time (d=rt) to find the number of miles per hour Etty must drive to go 45 miles in 35 minutes. ( remember time is written in hours?"</em>

distance=rate*time--- we know distance and time

45 mi= rate*35

rate=45/35

rate=1.28571428571 miles per minute, or 77.1428571429 mph

8 0
3 years ago
you have decided to purchase a car for $15,699. the credit union requires a 10% down payment and will finance the balance with a
ycow [4]
Its D! Hope this helps :))
8 0
3 years ago
I fr need help I don’t know the answer
EastWind [94]

Answer:The answer is D

Step-by-step explanation:

3 0
3 years ago
Read 2 more answers
Other questions:
  • What is (81x^2 -4y^2) square units factored?
    14·1 answer
  • Round 43.586 to nearest thousandths
    9·2 answers
  • Whats a formula for four is no less than the quotient of a number x nd 2.1
    10·1 answer
  • 60,000 ones equals how many thousands
    15·1 answer
  • Combine value to find 615 minus 342
    12·1 answer
  • Write the number 0.00003852 in standard form
    7·1 answer
  • NEED HELP ASAP, WILL GIVE BRAINLIEST TO CORRECT ANSWER
    9·1 answer
  • What is the area of a rectangle that is 4 inches by 2 inches?
    8·1 answer
  • PLEASE HELP ASAP, MARKING BRAINLIEST!!!
    5·1 answer
  • Help! i’ll mark the right one as brainliest :)!
    5·2 answers
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!