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3 years ago

9

Mr. Rifkin had 240 digital and manual cameras. After donating 82 digital cameras and 26 manual cameras, he had three times as ma

ny digital cameras as manual cameras left. How many digital cameras did he have to begin with?

2 answers:

Rina8888 [55]3 years ago

4 0

Answer:

181

Step-by-step explanation:

puteri [66]3 years ago

3 0

After the donation,
3m + m = 132
manual = 33
digital = 99

Before the donation, he had 82 more digital and 26 more manual cameras.
82 + 99 = 181 digital
26 + 33 = 59 manual
For a double check, before donation,
digital + manual = 240
181 + 59 = 240
So, to begin with, the number of digital cameras = 181.

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Answer:

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Step-by-step explanation:

<u>Cramer's Rule</u>

It's a predetermined sequence of steps to solve a system of equations. It's a preferred technique to be implemented in automatic digital solutions because it's easy to structure and generalize.

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$\Delta=\begin{vmatrix}1 &1 \\1 &-2 \end{vmatrix}=-2-1=-3$

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$\displaystyle y=\frac{\Delta_y}{\Delta}=\frac{3}{-3}=-1$

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$\displaystyle \left \{ {{4x-y=6} \atop {x-y=0}} \right.$

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$\Delta=\begin{vmatrix}4 &-1 \\1 &-1 \end{vmatrix}=-4+1=-3$

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3 years ago

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valentinak56 [21]

Answer: 6.71

=======================================

Work Shown:

The longest horizontal portion of length 6 breaks up into two equal pieces of length 3 each. Focus on the smaller right triangle on the right hand side. This right triangle has legs of 3 and 6. The hypotenuse is x.

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