Answer:

Step-by-step explanation:
we know that
An <u><em>equilateral triangle</em></u> has three equal sides and three equal interior angles (each interior angle measure 60 degrees)
so
The perimeter is equal to

where
b is the length side of the equilateral triangle
we have

substitute

solve for b

Find the area
The formula of area applying the law of sines is equal to

substitute the value of b




Answer:
The mean is 7.975.
Step-by-step explanation:
<h3>
Answer: x = 21</h3>
Explanation:
The two angles shown combine to 180 degrees because the angles form a straight line.
(3x+18)+(4x+15) = 180
7x+33 = 180
7x = 180-33
7x = 147
x = 147/7
x = 21
ANSWER: Multiply and Divide from left to right
To do this question we must follow the rules of PEMDAS. The first step would be to evaluate the equation given to us in the parentheses. To solve that we would have to use PEMDAS once again which tells us to multiply 2 x 2 before we add 3, so we get 7. Now that there is no more Parentheses, our second step is to evaluate each Multiplication and Division expression from left to right. This would start by dividing 63 by 7 to get 9.