Find 26th term in the arithmetic sequence: - 15,-35,-55,-75, ...

-515

Step-by-step explanation:

In this example the first value is - 15 and every value afterwards is 20 less.

After substituting these values to above formula, we obtain:

All we have to do is add 25 twenties or 25 x 20 = 500 and - 15 - 500 = - 515

Step-by-step explanation:

hello:

-75 - (-55) = (-55) - (-35) = (-35) - (-15) = -20

the ratio diff is : d=-20

the nth term is : An=A1 + (n-1) d A1 = -15

An=-15 + (n-1) (-20) = 15-20n+20

An = - 20n+5

26th term when : n=26 A26 = - 20 (26) + 5 = - 515

A26 = - 515