The cost of 5 apples is $6
4/7 = 8/14 = 12/21 = 16/28, etc
16x can be broken down into factors of -105.
21 and -5 come to mind.
7x² + 21x - 5x - 15
7x(x + 3) - 5(x + 3)
(7x - 5)(x + 3) is the factorised form.
Inequalities will have a <, >, <=, =>, = or will be worded as "Less than", "greater than", etc.
Equations must have mathematical functions and equal sign.
15=3x is an equation since 3x = 3*x
Finally, expressions are mathematical functions that have no equal signs.
