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
9/20. Add 20+24+36=80. Then it's 36/80. Divide both the bottom and the top by 4 and you get 9/20.
Answer: c
Step-by-step explanation:
Answer:
x = 10
The second number is 50
Step-by-step explanation:
Givens
The first number = x
The second number = 5x
Together when added the answer is 60
Equation
x + 5x = 60 Combine like terms
Solution
6x = 60 Divide by 6
6x/6 = 60/6
x = 10
Answer:
Step-by-step explanation:
So we have the equation:
First, let's distribute the left side of our equation:
Multiply:
Now, let's isolate the y-variable. Subtract 4y from both sides:
The right side cancels. Subtract on the left. So:
Now, subtract 5 from both sides:
The left side cancels. Subtract on the right:
Now, divide both sides by 6. So:
The left will cancel. Therefore:
And we're done!