The 8th term of an ap is 17 and 19 term is 39 find the common difference

2

Step-by-step explanation:

an = a1 + d(n-1) is the formula

17 = a1 +d(8-1 ) = a1 *7d

39 = a1 +d (19-1) =a1+ 18d

We have 2 equations and 2 unknown.  Subtract to eliminate a1

39 = a1 +18d

-17 = a1 +7d

22 = 11d

Divide by 2

22/11 = 11d/11

2 =d

The common difference is 2

check above link.

graphically?   well, you graph them both, the solutions is where they both intersect each other, since there are two solutions, meaning they will meet twice, or namely the linear will run into the quadratic curve twice, and where they meet, those x,y coordinates are the solutions to the system.