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3 years ago

Please help me. I’ll mark you as brainliest if correct

Mathematics

1 answer:

scZoUnD [109]3 years ago

7 0

Answer:

b = -18

Step-by-step explanation:

(3 + 4i) (-3-2i)

When we foil:

-9 + -6i + -12i + -8i^2

-8i^2 = +8

Combine like terms:

-1 + -18i

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Which equation is equivalent to 2/3(3x+9)=21

ivann1987 [24]

Answer:

2x+6=21 is equal to your equation

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2 years ago

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At westwood Middleschool, 648 students responded to a survey asking about their favorite type of exercise. Twice as many student

nalin [4]

Answer:

The number of students chose jogging is 144, chose swimming is 72, chose yoga is 144 and chose biking is 288.

Step-by-step explanation:

Given:

At westwood Middle School, 648 students responded to a survey asking about their favorite type of exercise.

Twice as many students chose jogging as swimming.

The same number of students chose yoga as jogging.

Twice as many students chose biking as jogging.

Now, to find the number of students chose each type of exercise.

Let the students chose jogging be $w.$

The student chose swimming be $x.$

The student chose yoga be $y.$

And the student chose biking be $z.$

As per given in question:

Twice as many students chose jogging as swimming.

$w=2x\\\frac{w}{2} =x\\$ .........(1)

The same number of students chose yoga as jogging.

$y=w$ .........(2)

Twice as many students chose biking as jogging.

$z=2w.$ .........(3)

Total students surveyed = 648.

According to question:

$w+x+y+z=648.$

Putting the value from above equations (1), (2) and (3) we :

$w+\frac{w}{2} +w+2w=648$

$4w+\frac{w}{2}=648$

$\frac{8w+w}{2} =648$

$\frac{9w}{2}=648$

Multiplying both sides by 2 we get:

$9w=1296$

Dividing both sides by 9 we get:

$w=144.$

The students chose jogging = 144.

The student chose swimming:

$x=\frac{w}{2} \\x=\frac{144}{2} \\x=72$

The students chose yoga:

$y=w\\y=144.$

The student chose biking :

$z=2w\\z=2\times 144\\z=288$

Therefore, the number of students chose jogging is 144, chose swimming is 72, chose yoga is 144 and chose biking is 288.

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2 years ago

Enrollment in a dance studio has grown exponentially since the studio opened. A graph depicting this growth is shown. Determine

denis23 [38]

Answer:

Option (4). 25%

Step-by-step explanation:

The graph attached shows the exponential growth.

Let the graphed function is y = $(1+\frac{r}{100})^{t}$

Here 'r' = Rate of growth

t = Duration of time in years

y = enrollments after time 't' years

Graph shows at time 't' = 0 or initially number of enrollments = 20

After 8 years number of enrollments will be

120 = $20(1+\frac{r}{100})^{8}$

$\frac{120}{20}=(1+\frac{r}{100})^{8}$

6 = $(1+\frac{r}{100})^{8}$

log 6 = $8\text{log}(1+\frac{r}{100})$

0.77815 = $8\text{log}(1+\frac{r}{100})$

$\text{log}(1+\frac{r}{100})$ = 0.0972689

$(1+\frac{r}{100})=1.251$

$\frac{r}{100}=0.251$

r = 25.1%

r ≈ 25%

Therefore, Option (4) will be the answer.

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2 years ago

A minibus drives with a constant speed of 80 miles per hour. How far can it travel in 2 1/2 hours?

deff fn [24]

Answer:

200 Miles

Step-by-step explanation:

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2 years ago

What is 48,100,000,000,000 in scientific notation?

vfiekz [6]

Scientific notation is
$x*10^b$ where 1≤x<10 and b is an integer

b is how many spaces you had to move the decimal to the left in the original number to obtain x

so
48,100,000,000,000
to
4.8100000000000
the decimal was moved 13 spaces
so b=13
a=4.81

in scientific notation, 48,100,000,000,000 is $4.81*10^{13}$

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2 years ago

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