Start with the following simple equation: a=b (step 1) Multiply both sides by b: ab=b2 (step 2) Subtract a2 from both sides and factorize: ab−a2=b2−a2 (step 3) a(b−a)=(b+a)(b−a) (step 4) Simplify and add 1 to both sides: a=b+a (step 5) a+1=b+a+1 Now since a=b (the starting point of this proof), we can write this as: a+1=2a+1 And in the case where a=1, we have: 1+1=2+1 So, therefore, 1+1=3

answer set (b) 0.5, 3/4 80% is in order from least to greatest.  

step-by-step explanation:

in order to compare rational numbers to each other, it is much easier if they are in the same form.   typically, the best form in which to evaluate rational numbers is in decimals.   in order to convert a percent to a decimal, you would divide the given percentage by 100.   you can also accomplish the conversion by moving the decimal point over two places to the left.   for example, the decimal value of 80% is 80/100, or 0.8.   in order to convert a fraction to a decimal, you need to divide the numerator by the denominator.   for example, 3/4 is 0.75.   so, for choice (b) 0.5 3/4 (0.75), 80% (0.8) is the only choice in which the numbers are in order from least to greatest.  

x= cost per bracelet

number of bracelets * x + shipping charge = total cost

so

9x+9=72