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

Find all complex solutions of the equation x^4 + x^2 - 6 = 0

who is Socrates? why was he put on trial? what was the outcome?

What is the probability of rolling an even prime number with one toss of a die? Thanks!!!

what are the only multicellular protists

in a pet store the number of dogs is 12 more than three times the number of cats. If the pet store has 21 dogs how many cats does it have

an ant sits on the back of a mouse. The mouse carries the ant across the floor for a distance of 10 meters. Was there work done by the mouse

what is a solid figure formed by 2 congruent parallel circles joined by a curved surface

Which describes the Eastern Woodland Indians? A. depended on buffalo B. lived in wigwams and longhouses C. found ways to farm the desert D. built tall, car

Sara can take no more than 22 pounds of luggage on a trip. Her suitcase weighs 112 ounces. How many more pounds can she pack without going over the limit?

When you add 18 to 1/4 of a number you get the number itself