Please explain the full equation

First two boxes are 6

Third box is -18

the last row is 3/1 (-18/1) = (1/3a) 3/1

Step-by-step explanation:

Ima try my best to explain:

-6 = 12 + 1/3a

+6    +6        

0 = 18 + 1/3 a    subtract 18 on both  in order to get 1/3a by itself

-18   -18

-18 = 1/3a          

-18/ 1/3  = 1/3a / 1/3 to make it easier multiply by the reciprocal on both sides

3/1 x -18/1 = 1/3 x 3/1      

multiply across will get you -54/1 which is just -54

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.  

the first one is x^2+2x+2

the second one is x^2+4

the last one is x^2-4x+8