D.985.2 is the correct answer
Answer:
a
n
=
−
2
n
+
15
Step-by-step explanation:
This is an arithmetic sequence since there is a common difference between each term. In this case, adding
−
2
to the previous term in the sequence gives the next term. In other words,
a
n
=
a
1
+
d
(
n
−
1
)
.
Arithmetic Sequence:
d
=
−
2
This is the formula of an arithmetic sequence.
a
n
=
a
1
+
d
(
n
−
1
)
Substitute in the values of
a
1
=
13
and
d
=
−
2
.
a
n
=
13
+
(
−
2
)
(
n
−
1
)
Simplify each term.
Tap for more steps...
a
n
=
13
−
2
n
+
2
Add
13
and
2
.
a
n
=
−
2
n
+
15
Subtract 39 from both sides
-7x = -4 - 39
Simplify -4 - 39 to -43
-7x = -43
Divide both sides by -7
x = -43/-7
Two negative make a positive
<u>x = 43/7</u>
<em>For the second equation;</em>
Simplify brackets
7x + 7 = 4
Subtract 7 from both sides
7x = 4 - 7
Simplify 4 - 7 to -3
7x = -3
Divide both sides by 7
<u>x = -3/7</u>
Answer:
sarah is correct
Step-by-step explanation:
there are not multiple ways to divide you can only use division and the equation is 15/2
