Answer:
The triangle has one solution. The remaining side c ≈ 4 and remaining angles B = 30°; C = 31°.
Option D is correct.
Step-by-step explanation:
if angle A is obtuse and if a > b then the triangle has one solution
We are given ∠ = 119° which is obtuse and side a= 7 and side b - 4 i.e 7>4 so, the triangle has one solution.
Finding remaining side c and ∠B and ∠C
Using Law of sines to find ∠B
a/sin A = b/sin B
7/sin 119° = 4/sin B
7 * sin B = 4 * sin 119
7*sin B = 4(0.874)
sin B = 3.496/7
B = sin^-1(0.4994)
B = 29.96 = 30°
We know that sum of angles of triangle = 180°
So, 180° = 119° + 30° +∠C
180° = 149° + ∠C
=> ∠C = 180° - 149°
∠C = 31°
Now finding c
b/sin B = c /sin C
4/Sin 30 = c/sin 31
4* sin 31 = c*sin 30
4*0.515 = c* 0.5
=> c = 4*0.515/0.5
c = 4.12 ≈ 4
So, Option D one solution; c ≈ 4; B = 30°; C = 31° is correct.
Let the number be x.
Triple the number means 3x
add 6 means 3x + 6
subtract the number twice 3x + 6 - x - x
the result is the number plus 3 means that the result is x + 3
So, combining these into an equation, we get:
3x + 6 - x - x = x + 3
If we solve this equation for x, we will get:
x + 6 = x + 3
The x will cancel out and we will get : 6 = 3
Therefore, this is a false statement.
Hi
The solution to this is
-6x - 90
I am not sure if you want more than one answer.
Just let me know if this helps
Answer:
See the proof below.
Step-by-step explanation:
For this case we just need to apply properties of expected value. We know that the estimator is given by:
And we want to proof that 
So we can begin with this:
And we can distribute the expected value into the temrs like this:
And we know that the expected value for the estimator of the variance s is 
, or in other way 
so if we apply this property here we have:
And we know that 
so using this we can take common factor like this:
And then we see that the pooled variance is an unbiased estimator for the population variance when we have two population with the same variance.
