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Neporo4naja [7]
3 years ago
8

Oi can someone help me with this one ^{2}-12x-28=0 This is still pretty confusing for me

Mathematics
1 answer:
aleksley [76]3 years ago
5 0

Answer:

Both answers should be -2 and 14.

Step-by-step explanation:

Using the quadratic formula:

x^{2}-12x-28=0\\\\x=\frac{-(-12)+-\sqrt{(-12)^2-4(1)(-28)} }{2(1)}\\\\x= \frac{12+-\sqrt{144+112} }{2}\\\\x= \frac{12+-\sqrt{256} }{2}\\\\x= \frac{12+-16 }{2}\\\\x=6+-8

Therefore:

x_{1} =6+8=14\\x_{2}=6-8=-2

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Ksenya-84 [330]

Answer:  14.29%

Step-by-step explanation:

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Profit percentage would be (P/S)*100%

---------------------------------------------------------

We know that 21C = 18S:  This can be written as C = (18/21)S

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3 years ago
Devon made a scale drawing of a triangle. He used a scale factor of 1/4 to draw the new triangle. How does each side of the new
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The answer is Option A.
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Adjustment of distance between promoter and cloned gene.

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