The surface area of a sphere with radius r is four times the product of pie and the square of the radius?

Question

Identify the terms, coefficients, and constants. Determine if the expression is quadratic. Why or why not.

Answer 1

A = 4Πr^2

Constant: In Algebra, a constant is a number on its own, or sometimes a letter such as a, b or c to stand for a fixed number. Example: in "x + 5 = 9", 5 and 9 are constants.

Coefficient: A number used to multiply a variable. Example: 6z means 6 times z, and "z" is a variable, so 6 is a coefficient. Variables with no number have a coefficient of 1. Example: x is really 1x

Term:

In elementary mathematics, a term is either a single number or variable, or the product of several numbers or variables. Terms are separated by a + or - sign in an overall expression

So, here the term is 4Πr^2

Answer 2

Translate the verbal description into algebra. Pick whatever letters you like to stand in for things. For example, you could write:

S = 4πr²

This expression outputs the surface area (S) given the input of the radius (r). Now, according to Wikipedia, "quadratic" comes from the Latin quadratus for "square". Is r being squared?