Question

Solve the equation for:
x: 2+5+8+...+x= 155

Answer 1

Answer:

X=10

hope it helps......

Answer 2

Answer:

29

Step-by-step explanation:

2 + 5 + 8 + . . . . . . + x = 155

a = 2, d = 5 - 2 = 3, Sₙ = 155, n = ?, x = ?

Sₙ = $\frac{n}{2}$(2a + (n - 1)d)

155 = $\frac{n}{2}$(4 + 3n - 3)

solving the equation we will get n = 10 and n = $\frac{-31}{3}$

Rejecting n = $\frac{-31}{3}$; we will have n = 10

Now,

Sₙ = $\frac{n}{2}$(a + l)

155 = $\frac{10}{2}$(2 + x)

solving the equation we will get x = 29.

Hope this answer was helpful to you.

If it is helpful Please don't forget to mark this answer as Brainliest.

Thank You.