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3 years ago

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Mathematics

2 answers:

Lesechka [4]3 years ago

8 0

Answer:

Step-by-step explanation:

x² – 8x – 9 = 0
x² – 8x = 9
x² – 8x + 16 = 9 + 16
(x – 4)² = 25
x – 4 = 25 and x – 4 = - 25 ⇒ Incorrect, should be x - 4 = 5 and x - 4 = -5
x = 29 and x = -21 ⇒ Incorrect, should be x = 9 and x = -1

earnstyle [38]3 years ago

7 0

Answer:

No, it's wrong

${x}^{2} - 8x - 9 = 0 \\ (x - 9)(x + 1) = 0 \\ x = 9 \: and \: - 1$

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Write the equation of the line in fully simplified slope intercept form

yan [13]

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The standard equation of a line in slope-intercept form is expressed as

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m is the slope of the line

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Using the coordinate point (0, -2) and (-6, 3)

Slope m = 3-(-2)/-6-0

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2 years ago

A silversmith combined pure silver that cost $33.48 per ounce with 51 oz of a silver alloy that cost $24.35 per ounce. How many

Pavlova-9 [17]

Answer:

$38.31

Step-by-step explanation:

Given:

Pure silver that cost $33.48 per ounce used to form $24.35 alloy/ounce.

Question asked:

How many ounces of pure silver were used to make an alloy of silver costing $27.87 per ounce?

Solution:

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Answer:

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Step-by-step explanation:

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