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natta225 [31]
3 years ago
7

8х + 5у = -7 — 7х + бу = — 4

Mathematics
1 answer:
Levart [38]3 years ago
7 0

Answer: x = -0.2651 and y = -0.9759

Step-by-step explanation:

Solution by substitution method

8x+5y= -7

-7x+6y= -4 = 7x-6y=4

Suppose,

8x+5y=-7→(1)

7x-6y=4→(2)

Taking equation (1), we have

8x+5y= -7

⇒8x= -5y -7

⇒x= -5y-7 / 8 →(3)

Putting x= -5y-7 / 8

in equation (2), we get 7x-6y=4

7(-5y-7/8)-6y=4

⇒-35y-49-48y=32

⇒-83y-49=32

⇒-83y=32+49

⇒-83y=81

⇒y= 81 / -83

⇒y= -0.9759→(4)

Now, Putting y= -0.9759 in equation (3), we get

x= -5y-7

x= -5(-0.9759)-7/8

⇒x= 4.8795-7/8

⇒x= -2.1205/8

⇒x= -0.2651

∴x= -0.2651 and y = -0.9759

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2 years ago
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zysi [14]

Answer:

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Step-by-step explanation:

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<em>Comment on percentages</em>

A percentage is a pure number. It is a ratio of like quantities, so has no units.* A <em>useful</em> percentage always has a base. That is, it is a percentage <em>of something</em>. Sometimes that base may be unclear or unstated, in which case the percentage might very well be considered to be meaningless.

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* The concentration or potency of some medicines or other mixtures may be expressed as a percentage that is the ratio of one unit to a different unit, typically weight per volume. That is, a "0.1%" preparation may be 0.1 grams per 100 mL, for example. You have to read the label to determine whether this is the case. Mathematically, this is not a percentage, but is a non-standard use of the "%" symbol to indicate a ratio to 100 of something.

4 0
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eimsori [14]

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Step-by-step explanation:

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3 years ago
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AVprozaik [17]

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If my answer was helpful, please mark it as brainliest.

3 0
2 years ago
Read 2 more answers
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