3 years ago

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

1 answer:

5 0

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

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Help please this question is so hard!

Nitella [24]

So to solve this first you need to convert all the answers to decimals.
Site B 17/9 = 1.89 when you round up
Site D 4/3 = .75
Then look at all the numbers least to greatest.
D .75 m C 1.36 m A 1.60 m B 1.89 m
Answer D, C, A, B

6 0

3 years ago

What is the y-intercept of the line whose equation is y = –2x + 8?

g100num [7]

Answer:

(0,8)

Step-by-step explanation:

y = –2x + 8

The y intercept is found when x =0

y = –2*0 + 8

y = 8

The y intercept is