Quadratic is in the form
ax^2+bx+c=0
so distribute and stuff and simplify
remember
a(b+c)=ab+ac
(x+2)^2+5(x+2)-6=0
remember order of opertaions
(x+2)(x+2)+5(x+2)-6=0
x^2+4x+4+5x+10-6=0
add like terms
x^2+9x+8=0
The answer is 13
If R=4 the the equation would be 4+9 which equals 13.
The atomic mass of an element is the average mass of the atoms of an element measured in atomic mass unit (amu, also known as daltons, D). The atomic mass is a weighted average of all of the isotopes of that element, in which the mass of each isotope is multiplied by the abundance of that particular isotope. (Atomic mass is also referred to as atomic weight, but the term "mass" is more accurate.)
C=Pi X D
Diameter is twice the radius so that would be 24 feet
C = Pi X 24
C = (22/7) X 24
C = 75.428 Feet.