Because zero is neither positive nor negative, the term nonnegative is sometimes used to refer to a number that is either positive or zero, while nonpositive is used to refer to a number that is either negative or zero. Zero is a neutral number.
Answer,a and b, sorry if they are wrong
Step-by-step explanation:
price difference= $45-$36
=$9
now,
x% of $45=$9
or, x/100 ×45 =9
or, x/20 ×9=9
or, x/20=1
therefore, x= 20%
2x+1.....i think,let me know
