Answer:
Step-by-step explanation:
If it is a parallelogram the opposite sides will a have the same slope.
Using the diagram we see from the coordinates of A and B:
Slope of AB = (5 - -1)/(-1 - -5)
= 6/4
= 3/2.
In the same way
slope of CD = (2 - -4) / (1 - -3)
= 3/2.
So AB and CD can be shown to be parallel.
Similarly the lines BC and AD are parallel.
So the figure is a parallelogram
Finding the perimeter (counting the units between the points):
Perimeter = 2AB + 2BC
By Pythagoras:
AB = sqrt (6^2 + 4^2) = sqrt 52
BC = sqrt (3^2 + 2^2) = sqrt 13
So Perimeter = 2sqrt52 + 2sqrt13
= 4sqrt13 + 2 sqrt13
= 6sqrt13
or 21.63 unit^2 to 2 decimal places.
Area = sqrt52 * perpendicular distance between the lines AB and CD.
Answer:
12566.4 mm²
Step-by-step explanation:
The Petri dish shown has no lid. What is the surface area of the outside of the Petri dish? Round to the nearest tenth. A cylindrical-shaped Petri dish with a radius of 50 millimeters and a height of 15 millimeters.
TSA = Total Surface Area
CSA = Curved Surface Area
TSA of open cylinder = CSA of cylinder + area of base or top
= 2πrh + πr²
= πr(2h + r)
From the above question:
r = 50mm
h = 15mm
Hence,
= π × 50 (2 × 15 + 50)
= π × 50 (30 + 50)
= π × 50(80)
= π × 4000
= 12566.370614mm²
Approximately = 12566.4 mm²
The Surface Area of the petri dish with no lid = 12566.4 mm²
Answer:
Approximately, the 90% confidence interval for the students' mean IQ score is between 129.045 - 130.956
Step-by-step explanation:
The formula to use to solve this question is called the Confidence Interval formula.
Confidence interval =
x ± z × ( σ/ (√n) )
Where:
x = the sample mean = 130
z = the z-value for 90% confidence = 1.645
σ = standard deviation = 7
n = sample size = 145
130 ± 1.645 × (7/√145)
130 ± 0.9562687005
130 - 0.9562687005 = 129.0437313
130 + 0.9562687005 = 130.9562687005
Therefore, approximately, the 90% confidence interval for the students' mean IQ score is between 129.045 - 130.956