The area of triangle ABC ABC is 18 cm2. Side AC=4x AC = 4 x and side AB=x+3 AB = x + 3 . Given that angle A=30∘ , calculate the
1 answer:
Answer:
x = 3
Step-by-step explanation:
Let the altitude from B to AC intersect at point D. Then BD is a height of the triangle with base AC
ΔABD is a 30-60-90 triangle since m∠A = 30
Therefore, AB = 2(BD) or BD = AB/2 = (x+3)/2
Area of the triangle = bh/2 = AC(BD)/2 = 4x(x + 3)/(2)(2)
= x(x + 3) = 18
(x + 6)(x - 3) = 0
x = -6 or x = 3
x cannot equal -6, so x = 3
You might be interested in
Answer:
Step-by-step explanation:
The model , the number of planets found up to time
, as a Poisson process. So, the
has distribution of Poison distribution with parameter
a)
The mean for a month is, per month
(Here. t = 24)
For Poisson process mean and variance are same,
(Poisson distribution mean and variance equal)
The standard deviation of the number of planets is,
b)
For the Poisson process the intervals between events(finding a new planet) have independent exponential distribution with parameter . The sum of
of these independent exponential has distribution Gamma
.
From the given information, and
Calculate the expected value.
(Here, and
)
C)
Calculate the probability that she will become eligible for the prize within one year.
Here, 1 year is equal to 12 months.
P(X ≤ 12) = (1/Г (k)λ^k)(x)^(k-1).(e)^(-x/λ)
Hence, the required probability is 0.2149 or 21.49%