The sum of third and seventh terms of an AP is 20 . Find the sum of the first nine

Given:

The sum of third and seventh terms of an AP is 20.

To find:

The sum of the first nine terms.

Solution:

We have, the sum of third and seventh terms of an AP is 20.

       ...(i)

nth term of an AP is

where, a is first term and d is common difference.

      ...(ii)

      ...(iii)

Using (i), (ii) and (iii), we get

        ...(iv)

Now, the sum of first n terms of an AP is

Put n=9 to find the sum of first 9 terms of an AP.

          [Using (iv)]

Therefore, the sum of the first 9 terms is 90.

answer: a) (0,0), (1,1), (2,8), and (3,27).

step-by-step explanation:

0^3=0

1^3=1

2^3=8

3^3=27

in effect, the exponential equation for this would me y=3^x. each x-coordinate cubed is giving the y coordinate, so a is your answer : )

options a,b,c are the right answer.

step-by-step explanation:

a linear parent function is always represented as y = x

if we write this function in the form of y=mx+c

⇒

or  

now if we plot a graph we will find these characteristics:

1) y intercept of the graph is zero so its a straight line passing through origin.

2) as we can see in both the forms of function written, values of x and y may be either positive or negative for the positive slope means points on the graph are either in first quadrant or in third one.

3) it's slope is one.