First of all, you want the variable to be isolated, so in order to do that, you divide in both sides. Ten divided by two is five. So f = 5.
2f + 10
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2 2
10 divided by 2 = 5
Answer:
It is an arithmetic sequence and the common difference is 5
Step-by-step explanation:
4+5 = 9; 9+5=14 (adding is arithmetic, multiplying is geometric)
ANSWER

EXPLANATION
If ABCD is a parallelogram, then
line AB is parallel to line DC .
This means that,

and

are alternating angles.
Alternate angles are congruent.
This implies that,

We group like terms to obtain,

This simplifies to,

Also, if ABCD is a parallelogram then,
BC is parallel to AD. This means that,

We group like terms to get,

This simplifies to,

We divide both side by 4 to get,