Question

the first term of an arithmetic sequence is -5 and the tenth term is 13. Find the common difference.
A. 8/9
B. 1.8
C. 2

Answer 1

$a10 \: = \: a + 9d$
13 = -5 + 9d
d=2

Answer 2

Hey there !!


➡ Given:-

→ 1st term of AP ( $a \tiny 1$ ) = -5.

→ 10th term of AP ( $a \tiny 10$ ) = 13.


➡ To Find :-

→ The common difference (d) .


➡ Options :-

A. 8/9 .

B. 1.8 .

C. 2 . ✔✅✔✅


▶ Option C is the correct answer. .i.e., 2.


➡ Explanation :-

→ $a \tiny 1$ = -5.

→ $a \tiny 10$ ) = 13.

=> a + 9d = 13.

[ putting the value of a ].


=> -5 + 9d = 13.

=> 9d = 13 + 5.

=> 9d = 18.

=> d = $\frac{18}{9} .$

$\huge \boxed{ \boxed{ \bf \therefore d = 2. }}$


✔✔ Hence, it is solved ✅✅.

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#BeBrainly.