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3 years ago

Why does -4i*i=4? what happens to the i when you multiply it

Mathematics

1 answer:

Alchen [17]3 years ago

8 0

$▪ ▪ ▪ ▪ ▪ ▪ ▪ ▪ ▪ ▪ ▪ ▪ ▪ { \huge \mathfrak{Answer}}▪ ▪ ▪ ▪ ▪ ▪ ▪ ▪ ▪ ▪ ▪ ▪ ▪ ▪$

As we know that :

${i}^{2} = i \times i = - 1$

so, over here

$- 4i \times i$

$- 4 {i}^{2}$

plugging the value of i² as -1

$- 4 (- 1)$

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The graph of f(x) is obtained by translating the graph g(x)=|x| five units down.

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F(x)=IxI-5
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3 years ago

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3 years ago

Help. Solving Multi Step Ratio Problems!

Romashka-Z-Leto [24]

Answer:

Part 1) $30\ coupons$

Part 2) $12\ sandwiches$

Part 3) $60\ push-ups$

Part 4) $96\ minutes$

Part 5) $\$95$

Part 6) $1\frac{7}{8}\ cups\ of\ pretzel$

Step-by-step explanation:

Part 1) we know that

At the Green House of Salad , you get a $1 coupon for every 3 salads you buy

Using proportion

Find out the number of salads you could buy to get $10 in coupons

$\frac{1}{3}=\frac{10}{x} \\\\x=3(10)\\\\x=30\ coupons$

Part 2) we know that

Kim orders catering for $35

She spend $5 on a large order of potato salad and the rest on turkey sandwiches

Each sandwich is $2.50

How many sandwiches does Kim buy?

step 1

Find out how many Kim spent on turkey sandwiches

Subtract $5 from $35

35-5=$30

step 2

Using proportion, find out the number of sandwiches

$\frac{1}{2.50}=\frac{x}{30}\\\\x=30/2.50\\\\x= 12\ sandwiches$

Part 3) we know that

Molly does 10 push-ups at the same time as Liza does 15 push-ups

Using proportion

Find out how many push-ups Liza does when Molly does 40 push-ups

$\frac{10}{15}=\frac{40}{x}\\\\x=15(40)/10\\\\x=60\ push-ups$

Part 4) we know that

A shark swim at a speed of 25 miles per hour

The shark rest after 40 miles

How long in minutes, does the shark swim before resting?

Using proportion

Find out how long in minutes the shark swim 40 miles

Remember that

$1\ h=60\ min$

$\frac{25}{60}\ \frac{miles}{minutes}=\frac{40}{x}\ \frac{miles}{minutes}\\\\x=60(40)/25\\\\x=96\ minutes$

Part 5) we know that

For every bar of soap that Aly sells, she earns $5

For every mug that Janet sells, she earns twice as much as Aly

Aly sells 5 bars of soap and Janet sells 7 mugs

How much money did they make altogether?

step 1

Find out the amount earned by Aly

using proportion

$\frac{1}{5}=\frac{5}{x}\\\\x=5(5)\\\\x=\$25$

step 2

Find out the amount earned by Janet

Remember that

For every mug that Janet sells, she earns twice as much as Aly

For every mug that Janet sells, she earns 2($5)=$10

using proportion

$\frac{1}{10}=\frac{7}{x}\\\\x=10(7)\\\\x=\$70$

step 3

Adds the amount earned by Aly plus the amount earned by Janet

$25+70=\$95$

Part 6) we know that

Ted is making trail mix for a party

He mixes 1 1/2 cups of nuts, 1/4 cup of rising and 1/4 cup of pretzel

How many cups of pretzel does Ted need to make 15 cups of trail mix?

Adds the quantities

$1\frac{1}{2}+\frac{1}{4} +\frac{1}{4}=2\ cups\ of \ trail\ mix$

That means

For every 2 cups of trail mix we need 1/4 cup of pretzel

using proportion

Find out how many cups of pretzel does Ted need to make 15 cups of trail mix

$\frac{2}{(1/4)}=\frac{15}{x}\\\\x=15(1/4)/2\\\\x=\frac{15}{8}\ cups\ of\ pretzel$

Convert to mixed number

$\frac{15}{8}=\frac{8}{8}+\frac{7}{8}=1\frac{7}{8}\ cups\ of\ pretzel$

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4 years ago

The number of bacteria, B, in a refrigerated food is given by the function b(t) = 15t2 - 60t + 125, where t is the temperature o

Nimfa-mama [501]

Answer: $b(t(h))=135h^2+180h+125$

Step-by-step explanation:

Given: The number of bacteria, B, in a refrigerated food is given by the function $b(t)=15t^2-60t+125$ , where t is the temperature of food in degrees Fahrenheit.

The function $t(h)=3h+4$ gives the temperature, t, of the food h hours after being removed from the refrigerator.

Now, the number bacteria in the food in h hours is given by:-

$b(t(h))=15(3h+4)^2-60(3h+4)+125\\=15(9h^2+16+24h)-180h-240+125\\=135h^2+240+360h-180h-240+125\\=135h^2+180h+125$

So, The number bacteria in the food in h hours is given by:

$b(t(h))=135h^2+180h+125$

4 0

3 years ago

Help please!! percentages thank you!!

Zanzabum

Answer:

16=25%

x=100%

25x=1600

x=64

6300/1260 * 100 = 20

100 - 20 = 80%

Total: 40

Set desingers: 16

16/40 = 40%

500*22%=110

500-110=390

Hope this helped you! I would appreciate a Brainliest, if this answer helped you out!

7 0

2 years ago

Read 2 more answers