# 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 (ab) 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, a2 + b2 = c2.

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.

A formula for finding the roots of a quadratic equation:

A polynomial of degree two.

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

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

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.