pemdas: parentheses, exponents, (multiplication, division), (addition, subtraction)
a*d = c*b
a/b = c/d
b=ac, c=b/a
it's distance from 0
((NN - ON)/ON) * 100
Discount=OriginalNumber*RateOfDiscount
interest=principal*rate*time
a(b+c) = ab+ac
numbers that cant be expressed as a fraction
non-repeating non-terminating decimal. no exact place on number line
sqrt y: x < y < z (x and z = closest perfect square). outcome closest to y