None of your options, not via complete the square nor quadratic the formula.
Solve for x over the real numbers:
x^2 + 8 x + 9 = 0
x = (-8 ± sqrt(8^2 - 4×9))/2 = (-8 ± sqrt(64 - 36))/2 = (-8 ± sqrt(28))/2:
x = (-8 + sqrt(28))/2 or x = (-8 - sqrt(28))/2
sqrt(28) = sqrt(4×7) = sqrt(2^2×7) = 2sqrt(7):
x = (2 sqrt(7) - 8)/2 or x = (-2 sqrt(7) - 8)/2
Factor 2 from -8 + 2 sqrt(7) giving 2 (sqrt(7) - 4):
x = 1/22 (sqrt(7) - 4) or x = (-2 sqrt(7) - 8)/2
(2 (sqrt(7) - 4))/2 = sqrt(7) - 4:
x = sqrt(7) - 4 or x = (-2 sqrt(7) - 8)/2
Factor 2 from -8 - 2 sqrt(7) giving 2 (-sqrt(7) - 4):
x = sqrt(7) - 4 or x = 1/22 (-sqrt(7) - 4)
(2 (-sqrt(7) - 4))/2 = -sqrt(7) - 4:
Answer: x = sqrt(7) - 4 or x = -sqrt(7) - 4_____________________________________________________
Solve for x:
x^2 + 8 x + 9 = 0
Subtract 9 from both sides:
x^2 + 8 x = -9
Add 16 to both sides:
x^2 + 8 x + 16 = 7
Write the left hand side as a square:
(x + 4)^2 = 7
Take the square root of both sides:
x + 4 = sqrt(7) or x + 4 = -sqrt(7)
Subtract 4 from both sides:
x = sqrt(7) - 4 or x + 4 = -sqrt(7)
Subtract 4 from both sides:
Answer: x = sqrt(7) - 4 or x = -4 - sqrt(7)
Answer:
There are many.
Step-by-step explanation:
When you say proportional, you are looking for a ratio that is equivalent to the ratio given. In your case, there are many so you might need to be more specific. But still, we can help you figure it out.
An easy way to do this would be to scale it down to its simplest form and then move upwards. To find proportional ratios, just multiply denominator and the denominator with the same factor.
That is your ratio in its simplest form. Now we can scale up, I'll show you how to do one completely:
That's the same ratio scaled up by a factor of 2.
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That's the ratio given
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Scaled up by a factor of 4
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Scaled up by a factor of 5.
The list goes on and on.
Answer:
78 mg
Step-by-step explanation:
370 mg - 110 mg = 260 mg (amount decayed in the 8 total years)
260 mg ÷ 8 years = 32.5 mg decayed per year
32.5 × 9 years (years between 2008 and 2017) = 292.5 mg
370 mg - 292.5 mg = 77.5 mg, rounded to 78 mg
Answer:
oh ok thanks for free points
Step-by-step explanation: