# Squares and Square Roots Terms

## Get down with the lingo

### Conjugate

Radical expressions that are identical except for the plus/minus sign in the middle. Expressions like (*a*+

*b*) and (

*a*–

*b*) are conjugates. They're sort of the evil twins of the math world.

### Distributive Property

Multiplication of numbers that distributes over addition and subtraction:*a*(

*b*±

*c*) =

*ab*±

*ac*.

### Equations

An expression that states the equivalence of two algebraic expressions.### Equivalent Equations

Different equations that have the same solution(s).### Extraneous Solution

A solution to an equation that's formed in the process of simplifying the original equation (for example, taking the square of a radical equation), but is not a valid solution of the original equation. These guys are the worst: they seem like legit solutions when we solve for our variable, but then they run away and scream, "Not!" when we try to plug them back into the equation.### Factoring

Breaking up an algebraic expression into two or more expressions that can be multiplied together to get the original expression.### Like Terms

Two terms with the exact same radical. If the stuff inside the radical (the radicand) matches, we can combine those terms just like we do with like variables.### Principal Square Root

The positive square root of a number. Way more useful in real-life situations than their negative brethren.### Pythagorean Theorem

The fact that the sum of the squares of a right triangle's legs is equal to the square of its hypotenuse. Or as most people would prefer to remember it,*a*

^{2}+

*b*

^{2}=

*c*

^{2}.

### Quadratic Equation

An equation obtained by setting a quadratic polynomial equal to zero. We can solve these beasts by factoring, completing the square, or busting out the quadratic formula.### Quadratic Formula

A formula for finding the roots of a quadratic equation:### Quadratic Polynomial

A polynomial of degree two.### Radical Equation

An equation with a variable that's contained inside a radical symbol. Usually seen toting around a skateboard and wearing a backwards ball cap.### Radical Sign

The symbol of a square root. It sort of looks like a really elaborate check mark: √.### Radicand

The value inside the radical symbol. For example, 5 is the radicand of .### Rationalizing The Denominator

Rewriting the fraction to get rid of the radical in the denominator.### Square

A number raised to the power of two.### Square Root

The inverse operation of squaring a number.### Solution

Values that we can plug into a variable in an equation that make the equation true. Got a problem? Find the solution.### Variable

A value that changes. Variables are commonly represented by the letters*x*,

*y*, or

*z*.