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Zina [86]
3 years ago
14

How do you simplify (-4i)(7i)?

Mathematics
2 answers:
8090 [49]3 years ago
5 0

\bf (-4i)(7i)\implies -28i^2\implies \stackrel{\textit{recall that }i^2 = -1}{-28(-1)}\implies 28

xxTIMURxx [149]3 years ago
4 0

For this case we must simplify the following expression:

(-4i) (7i)

We have to by definition that:

- * + = -\\- * - = +\\i ^ 2 = -1

So:

-4i * 7i = -28i ^ 2 = -28 (-1) = 28

Finally we have that the expression is equivalent to:

(-4i) (7i) = 28

Answer:

(-4i) (7i) = 28

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Jamie needs to build a fence around his garden, as illustrated by polygon ABCDEF on the coordinate grid below. If each unit repr
hodyreva [135]

Answer:

I just had this problem on a test! I hope this helps, i will attach a picture of my messy work, but hopefully that will give you an idea on how do do it!

How to Solve!-

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5 0
3 years ago
Need help with math probelm if do 5 stars and brainly points
PtichkaEL [24]

Step-by-step explanation:

let's first convert feet to inches

4 ft = 48 inches ( width )

6.5 ft = 78 inches ( length )

12.5 ft = 150 inches ( height )

each cube is 1/4 x 1/4 x 1/4

x-axis ( length )

78 ÷ 1/4 = 78 x 4 = 312 cubes

y-axis ( width )

48 x 4 = 192 cubes

z-axis ( height )

150 x 4 = 600 cubes

the total number of cubes fit in the closet is :

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6 0
2 years ago
If you take 2 1/2 tablets of meds 3 times a day for 10 days, how many tablets in total have you taken?
Alisiya [41]
This is how I solved it.
2.5 multiplied by 3 is 7.5, which equals how many she takes a day.
Then I multiplied 7.5 by 10 = 75. I did that because the meds are taken for 10 days. 
Also if you added 7.5 ten times is also 75.

So my final answer is that 75 tablets have been taken in total.

3 0
3 years ago
Using number lines 80 is 25% of what number
Goshia [24]
25% can be made in to 100% by multiplying it by 4.

Therefore, we can find the answer by multiplying 80 by 4.


80 * 4 = 320
3 0
3 years ago
(01.02 MC)Maya is showing her work in simplifying (5.2 − 4.5) − 5.5 + 4.8. Identify any error in her work or reasoning. Step 1:
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I think it's the third one b/c the associative property states that it doesn't matter how you group the numbers in parenthesis in addition.
3 0
3 years ago
Read 2 more answers
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