Answer:
5+11i-16-4i+9i
5-16+11i-4i+9i
-11+7i+9i
-11+16i
Step-by-step explanation:
First, get the like terms together. Then add or subtract until its simplified. Simplified is -11+16i.
Answer: 230cm²
Step-by-step explanation:
>We can do this by splitting the figure into 2 trapeziums.
>Additionally, you can see that both trapeziums bear the same lengths a and b. Hence, we can use this formula:
.
>Thus,
Area = 
Answer:
Option B 13 units is correct.
Step-by-step explanation:
The formula used to find distance between 2 points is:
x₁ = 12 x₂ = 0 y₁= 9 and y₂=4
Putting values in the formula:

So, Option B 13 units is correct.
The 68-95-99.7 rule tells us 68% of the probability is between -1 standard deviation and +1 standard deviation from the mean. So we expect 75% corresponds to slightly more than 1 standard deviation.
Usually the unit normal tables don't report the area between -σ and σ but instead a cumulative probability, the area between -∞ and σ. 75% corresponds to 37.5% in each half so a cumulative probability of 50%+37.5%=87.5%. We look that up in the normal table and get σ=1.15.
So we expect 75% of normally distributed data to fall within μ-1.15σ and μ+1.15σ
That's 288.6 - 1.15(21.2) to 288.6 + 1.15(21.2)
Answer: 264.22 to 312.98