Answer all the questions below and press submit to see how many you got right.
Expression : An expression is a succession of constants, variables and mathematical operations that if evaluated for specific values of the variables represents a number.
Variable : A letter in an expression or function that represents an arbitrary number.
$2x^2-4x+4=?$ for $x=0$.
$2x^2+5x+1=?$ for $x=1$.
Assumption : An assumption is something that we assume to be true as part of trying to prove a statement. Assumptions play a critical role in proofs by induction and proof by contradiction.
Equation : An equation is a mathematical statement in which two expressions are written with an equal sign in between. A solution of an equation is a set of variables that makes the statement a true statement.
Multiple : A multiple of a number $x$ is any of the numbers $1x,2x,3x,4x,\ldots.$ For example the multiples of 7 include 7, 14, 21 and 70.
Multiplication : Multiplication is the mathematical operation that is a shorthand for adding the same amount several times. For example $3\cdot 4=4+4+4=12.$
Assume $x^2+2x-1=4$ for some $x$. Calculate $3x^2+6x-3.$