d = 3 , a₁₂ = 40 and S
= 7775
In an arithmetic sequence the nth term and sum to n terms are
<h3>• a
= a₁ + (n-1)d</h3><h3>• S
=
[2a + (n-1)d]</h3><h3>
where d is the common difference</h3><h3>a₆ = a₁ + 5d = 22 ⇒ 7 + 5d = 22 ⇒ 5d = 15 ⇔ d = 3</h3><h3>a₁₂ = 7 + 11d = 7 +( 11× 3) = 7 + 33 = 40</h3><h3>S₁₀₀ =
[(2×7) +(99×3)</h3><h3> = 25(14 + 297) = 25(311)= 7775</h3>
Answer:
2 to 12
Step-by-step explanation:
its not that hard
That I can not understand it looks weird.
Just matter of combining like terms
6x - 7 - 11x + x =
(6x + x - 11x) - 7 =
(7x - 11x) - 7 =
- 4x - 7 <===
The answer is A. just go by your placements
