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

What is the y-intercept of function g if g(x)=-4f(x)+12?

Which of the following pairs of organisms are most closely related A. sharks and amphibians B. primates and rabbits

If cost of 15 eggs is ? 75, then find out the cost of 4 dozens eggs. A 185 B 150 C 300 D 240

the scale on a map is stated as 1 : 250000 2 villages are 9 m apart on the map how far from each other are the two villages in kilomentres

show work plz answers i know just tell me the equation that equals the answer or explain all how to do it

A desk is on sale for $135.20, which is 26% of the regular price. What is the regular price?

Why was the damage to the South greater than the damage to the North during the war?

In a soccer game, lia takes 3 times as many shots as talisha. Talisha takes 5 shots how many shots dose lia take?

Find DB HELP ASAAPPP

Tim has 5 yellow and 10 blue marbles in a bag. What is the probability of randomly choosing a yellow marble from the bag? Enter your response as a fraction in l