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4 years ago

Even if I have use bidmas I'm still confuse with this equation (-7i)(2+i)+(2i)(-7i)

Mathematics

1 answer:

zheka24 [161]4 years ago

5 0

Assuming "i" is an imaginary unit:
$(-7i)(2+i)+(2i)(-7i)=\\
-14i+7+14=\\
21-14i$

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If y = 3 when x = 2. find x when y = 5.

ahrayia [7]

Y = 3 x = 2
if y = 1 x = ?

x = 3/2
x = 1.5
x = 5*1.5 ( y = 5 x = ?)
x = 7.5
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may be this can be that answer

x = 2/3
x = 0.67
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3 years ago

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Answer:

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3 years ago

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3 years ago

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The masses to the nearest 0.5 kg of two parcels are 1.5 kg and 2.5 kg .calculate the lower and upper bounds of their combined ma

Yanka [14]

Answer:

(3.5, 4.5)

Step-by-step explanation:

The masses have a total margin of 0.5 kg, or ±0.25 kg.

The mass of the first parcel is 1.5 kg ± 0.25 kg.

The mass of the second parcel is 2.5 kg ± 0.25 kg.

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3 years ago

The bus fare in a city is 1.75 . People who use the bus have the option of purchasing a monthly coupon book for . With the coupo

lorasvet [3.4K]

Answer:

26 times

Step-by-step explanation:

Given

Without Coupon

$Rate = 1.75$ per trip

With Coupon

$Coupon = 26$

$Rate = 0.75$ per trip

Required

The number of trips to be taken for both option (i.e. with or without coupon) to be equal

See comment for complete question

Let the number of trips in a month be x.

Without Coupon

Total amount is:

$Total = Rate * x$

$Total = 1.75x$

Without Coupon

Total amount is:

$Total = Coupon + Rate * x$

$Total = 26 + 0.75x$

To get x, we simply equate both options

$1.75x = 26 + 0.75x$

Collect like terms

$-0.75x + 1.75x = 26$

$x = 26$

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3 years ago