Answer:

Step-by-step explanation:
Subtract (6x-3y) from (9x+2y):

This can also be seen as:

Distribute the -1 to (6x-3y):

Simplify the parentheses:

Group like terms:

Combine:

This expression can't be further simplified. Therefore, 3x+5y is the answer.
:Done
We know that
[lateral surface area of a regular triangular pyramid]=3*[area of one <span>equilateral triangle]
so
[area of one </span>equilateral triangle]=lateral surface/3-----> 81/3-----> 27 ft²
[<span>surface area of the regular triangular pyramid]=lateral area+area of the base
area of the base is equals to the area of the lateral sides because are </span>equilateral triangles
therefore
area of the base=27 ft²
[surface area of the regular triangular pyramid]=81+27----> 108 ft²
the answer is
<span>the surface area of the regular triangular pyramid is 108 ft</span>²
Answer:
a≈18 cm
Step-by-step explanation:
we have given:
an angle,
the adjacent side and
we need to find:
the opposite side
we know that the definition of
tan of an angle = opp. side/ adj. side
tan 61° = a/ 10
multiply both sides by 10
10 * tan61° = a
18.04047755 = a
18 ≈ a
C) Major axis (because its facing your upper right)
The sample size suggested by this statement is 664 option second is correct.
<h3>What is the margin of error(MOE)?</h3>
It is defined as an error that provides an estimate of the percentage of errors in real statistical data.
The formula for finding the MOE:

Where Z is the z-score at the confidence interval
s is the standard deviation
n is the number of samples.
At 99% confidence Z = 2.576
By using the MOE formula:
0.05 = 2.376×√(0.5(0.5)/n)
After calculating
n = 663.57 ≈ 664
Thus, the sample size suggested by this statement is 664 option second is correct.
Learn more about the Margin of error here:
brainly.com/question/13990500
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