Answer: ∠B = 50°
∠BCD = 40°
<u>Step-by-step explanation:</u>
ACB is a right triangle where ∠A = 40° and ∠C = 90°.
Use the Triangle Sum Theorem for ΔABC to find ∠B:
∠A + ∠B + ∠C = 180°
40° + ∠B + 90° = 180°
∠B + 130° = 180°
∠B = 50°
BCD is a right triangle where ∠B = 50° and ∠D = 90°.
Use the Triangle Sum Theorem for ΔBCD to find ∠C:
∠B + ∠C + ∠D = 180°
50° + ∠C + 90° = 180°
∠C + 140° = 180°
∠C = 40°
The variance is the total of the squared distances of the given data from the mean.
This can be calculated through the equation,
σ² = summation of X² / N - μ²
where σ² is the variance X's are the data, N is the number of terms, and μ is the mean.
summation of X² = 100² + 100² + 120² + 120² + 180² = 81200
N = 5
μ = (100 + 100 + 120 + 120 + 180) / 5
μ = 124
Substituting these values to the equation for variance,
σ² = (81200/5) - 124² = 864
Thus, the variance is equal to 864.
Answer:
25.5 mi
Step-by-step explanation:
12 22.5 X
Let X be the shortest distance we are trying to find.
a units 2 b units 2 c units 2
12 units 2 + (22.5)=c units 2
144+506.25=c units 2
650.25=c units 2
=c units 2
25.5
