Question

please answer !!!!!?​

Answer 1

Answer:

S₆ = 120

Step-by-step explanation:

Given: a₁ = a = -5 and a₆ = 45

w.k.t., aₙ = a+(n-1)d, where a is first term and d is common difference of A.P.

⇒ a₆ = a+(6-1)d

or 45 = -5 + 5d

or 5d = 45+5 = 50

or d = 10

w.k.t., Sₙ = n*[2a + (n-1)d]/2

⇒ S₆ = 6 * [2(-5) + (6-1)d] /2

or S₆ = 3 * [-10 + 5*10]

or S₆ = 3 * [-10 + 50]

or S₆ = 3 * 40

or S₆ = 120

Please mark it as Brainliest.