3+ x, 9 + 3x, 13 + 4x, is an arithmetic sequence for some real number x.
a. find the value of x.

x = -2

Step-by-step explanation:

An arithmetic sequence is one where the difference between any two consecutive terms in the sequence is constant.

For any arithmetic sequence the general formula is as follow

where

is the nth arithmetic value

is the initial arithmetic value

is the nth term

is the difference is consecutive arithmetic values

To find the value of we form a number of simultaneous equations

from the given information we also know that

Solving these equations simultaneous we find the value of x to be

honesty mood

step-by-step explanation:

the answer is (-4,-4)

hope this ! : d