Answer: 
Step-by-step explanation:
We know that the standard quadratic equation is ax^2+bx+c=0
Let's compare all the given equation to it and , find discriminant.
1. a=2, b= -7, c=-9
So it has 2 real number solutions.
2. a=1, b=-4, c=4

So it has only 1 real number solution.
3. a=4, b=-3, c=-1

So it has 2 real number solutions.
4. a=1, b=-2, c=-8
So it has 2 real number solutions.
5. a=3, b=5, c=3

Thus it does not has real solutions.
What I would do is subtract 12 from -5. Then you would have -17. Then you would add 4 and it would be -13. So your answer is:
<h2><em>
-13</em></h2>
Answer:
linear
Step-by-step explanation:
Answer:
25
Step-by-step explanation:
The probability that a randomly selected adult has an IQ less than
135 is 0.97725
Step-by-step explanation:
Assume that adults have IQ scores that are normally distributed with a mean of mu equals μ = 105 and a standard deviation sigma equals σ = 15
We need to find the probability that a randomly selected adult has an IQ less than 135
For the probability that X < b;
- Convert b into a z-score using z = (X - μ)/σ, where μ is the mean and σ is the standard deviation
- Use the normal distribution table of z to find the area to the left of the z-value ⇒ P(X < b)
∵ z = (X - μ)/σ
∵ μ = 105 , σ = 15 and X = 135
∴ 
- Use z-table to find the area corresponding to z-score of 2
∵ The area to the left of z-score of 2 = 0.97725
∴ P(X < 136) = 0.97725
The probability that a randomly selected adult has an IQ less than
135 is 0.97725
Learn more:
You can learn more about probability in brainly.com/question/4625002
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