In Algebra we use letters to represent unknown numbers.
Something like 3x + 5y – 2z would be called an expression.
Something like 2x + 5 = 11 would be called an equation.
Every equation will only have one letter.
We can solve an equation to find the value of a letter.
Something like y =mx + c would be called a formula.
A few key words to remember
Simplify: When we take something slightly complicated and make it into a simpler term.
Solve: Solve means find the value of.
Substitute: We take information that we know and put it into one of our expression or formulae.
Expand: We expand an expression before we try to simplify it.