Mirella4mg Mirella4mg

01-08-2016
Mathematics

contestada

The third term of an arithmetic sequence is 21, and the eighth term is 56. The first term is

Respuesta :

dalendrk dalendrk

01-08-2016

[tex]a_3=21;\ a_8=56\\\\a_8-a_3=5d\\\\5d=56-21\\5d=35\ \ \ |divide\ both\ sides\ by\ 5\\d=7\\\\a_1=a_3-2d\\\\a_1=21-2\cdot7\\a_1=21-14\\a_1=7\\\\Answer:\boxed{a_1=7}[/tex]

Answer Link

Otras preguntas

Use the background information and diagram to answer the question: Which of the following are producers? 1Grass 2Algae 3Cyanobacteria 4Plankton

Multiplying a number by 9 and subtracting 6 is 16 less than twice the number. Find the number.

The diagram shows a right angle triangle 9cm 23 degrees what is the value of h

Which of the following is not a characteristic of specific phobia? a. The marked anxiety is far beyond what would be reasonable expected b. The stimulus is avo

if your here then pls help me i need it if not have a great day

find the n term of this number sequence 15 12 9 6

Mention 3 ways in which man-made damage to the lithosphere can be done and briefly explain how they can be prevented.

perimeter of square

A shop has an event where 80 items are on sale. Each item is discounted by up to £60. a) Find the upper and lower quartiles of the discounts. b) Find the interq

What did Rudy have to do to get free tutoring?