Answer:
A
Step-by-step explanation:
Recall that for a quadratic equation of the form:
The number of solutions it has can be determined using its discriminant:

Where:
- If the discriminant is positive, we have two real solutions.
- If the discriminant is negative, we have no real solutions.
- And if the discriminant is zero, we have exactly one solution.
We have the equation:

Thus, <em>a</em> = 2, <em>b</em> = 5, and <em>c</em> = -<em>k</em>.
In order for the equation to have exactly one distinct solution, the discriminant must equal zero. Hence:

Substitute:

Solve for <em>k</em>. Simplify:

Solve:

Thus, our answer is indeed A.
Given that,
The given expression is : 
To find,
The value of the above expression when x = 2 and y = 4
Solution,
We have,

Put x = 2 and y = 4 in the above expression.

So, the value of the above expression is 18.
Answer:
Step-by-step explanation:The probability of picking the biased coin: P(biased coin)=1/100. The probability of all three tosses is heads: P(three heads)=1×1+99×18100. The probability of three heads given the biased coin is trivial: P(three heads|biased coin)=1.
Answer:
Step-by-step explanation:
<em>Given that X - the distribution of heights of male pilots is approximately normal, with a mean of 72.6 inches and a standard deviation of 2.7 inches.</em>
<em />
<em>Height of male pilot = 74.2 inches</em>
<em />
<em>We have to find the percentile</em>
<em />
<em>X = 74.2</em>
<em />
<em>Corresponding Z score = 74.2-72.6 = 1.6</em>
<em />
<em>P(X<174.2) = P(Z<1.6) = 0.5-0.4452=0.0548=5.48%</em>
<em />
<em>i.e. only 5% are below him in height.</em>
<em />
<em>Thus the malepilot is in 5th percentile.</em>