What is the sum of the first 19 terms of the arithmetic series?
3+8+13+18+…
enter your answer in the box.

Step-by-step explanation:

The given arithmetic series is

The first term of this series is;

The constant difference is

The sum of the first n-terms of the sequence is

We plug n=19 and the other values to obtain;

the correct option is 2.

step-by-step explanation:

according to the given information triangle abc is a right angle triangle with right angle at a. segment ab is 5 and segment ac is 7. point d is on segment bc and angles adb and adc are right angles.

it is given that triangles abd, cad, and cba are similar.

two triangles are similar if their corresponding sides are proportional.

in triangle cba, using pythagoras theorem

                      )

triangle abd and cba are similar,

                            (2)

triangle cad and cba are similar,

                      )

using (1), (2) and (3), we get

hence proved.

therefore option 2 is correct.