Answer:
The radius 10 cm
Step-by-step explanation:
∵ The volume of the cone = 1/3 πr²h
∵ v = 1256 cm³
∵ h = 12 cm
∴ 1256 = 1/3 π (12) r²
∴ r² = 1256 × 3/12π = 100 cm
∴ r = √100 = 10 cm
If you need the sum than here is an equation for it 7x3= 21
One example is the equation 2x+3x = 5x because the left hand side combines to form the right hand side. This equation is said to be an identity, which is always true for any real number you can think of. For example, if x = 3, then,
2x+3x = 5x
2*3+3*3 = 5*3 ... replace every x with 3
6 + 9 = 15
15 = 15
We end up with a true equation. This will happen regardless of what x value we pick. Therefore, it has infinitely many solutions.
Answer:
2109 meter squared
Step-by-step explanation:

Answer:
k = 13
Step-by-step explanation:
The sum of the angles is 180 since they form a straight line
4k-7 + 90 + 3k+6 = 180
Combine like terms
7k+89=180
Subtract 89 from each side
7k+89-89 = 180-89
7k =91
Divide each side by 7
7k/7 = 91/7
k = 13