Expressions

Answer all the questions below and press submit to see how many you got right.

id: 9356

What is the value of the expression $x^2$ for $x=17?$

id: 9444

What is the value of the expression $(x+1)(x-1)$ for $x=15?$

id: 9402

What is the value of the expression $x-(-4)$ for $x=5?$