We are to solve the total area of the pyramid and this can be done through area addition. We first determine the area of the base using the Heron's formula.
A = √(s)(s - a)(s - b)(s - c)
where s is the semi-perimeter
s = (a + b + c) / 2
Substituting for the base,
s = (12 + 12 + 12)/ 2 = 18
A = (√(18)(18 - 12)(18 - 12)(18 - 12) = 62.35
Then, we note that the faces are just the same, so one of these will have an area of,
s = (10 + 10 + 12) / 2 = 16
A = √(16)(16 - 12)(16 - 10)(16 - 10) = 48
Multiplying this by 3 (because there are 3 faces with these dimensions, we get 144. Finally, adding the area of the base,
total area = 144 + 62.35 = 206.35
I think a decimal number line would help with subtracting and adding
Y= 2x+4, because when you plug in x and y you then solve for b and get 4. The 2x is the same because the slope stays the same on parallel lines.
Answer: x = 135 degrees and y = 225 degrees.
Step-by-step explanation: To solve this problem we first use the equation (n-2)*180 [n being the number of sides] to find the sum of interior angles in the figure. We plug the values in: (8-2)*180 = 6*180 degrees = 1080 degrees. We divide this by 8 to get the measure of an interior angle: 1080 degrees/8 = 135 degrees. Since all the interior angles of a regular polygon are congruent, we can say that angle x + angle y = 360 degrees. Thus subtract x degrees from 360 degrees to get y: 360 degrees - 135 degrees = 225 degrees. Therefore, x = 135 degrees and y = 225 degrees.
To find the interior angle of any regular polygon you can use the formula
where n is the number of sides
So,
The measure of an interior angle in a regular octagon is 135
