Which expression illustrates the associative property of addition? (3 19) â€"" 12 = (3 12) â€"" 19 3 (19 â€"" 12) = 3 (19 12) (3 19) â€"" 12 = 3 (19 â€"" 12) 3 (19 â€""12) = 3 â€"" (19 12).

, and

for

step-by-step explanation:

we can analyze the pattern at which the terms increase. let us denote , , , so that we can call

note the following:

the pattern: to get the next term value, we just add the next term number (e.g. 1st, 2nd, to the previous term value (term values are the given numbers in the question, 1, 3, 6, 10, 15,

from , to get to , we add

from , to get to , we add

etc.

we need to form a recursive formula, a formula that has the next term as a function of the previous term. so a possible recursive formula can be

, and for

x=-2

step-by-step explanation:

i began by flipping the problem to give me x= on the left (keeps it clearer for me).   so my problem simply became 10x-3=4x-6.  

1)   subtract 4x from the right side, which equals 0.   you do the same to the left of the equal as the right; therefore, subtract 4x from 10x, leaving 6x on the left.

              10x-3=4x-6   :   4x-4x on the right leaves only the -6        

2)             6x-3= 0-6 :    

                6x+3=   -6

3) divide