Question

I WILL MAKE YOU BRAINIST

Answer 1

Answer:

234

Step-by-step explanation:

We want to find the summation from n = 2 to n = 10 of the equation -4 + 5n.

We can use the summation formula:

$S=\frac{(a_1+a_n)*n}{2}$, where a1 is the first term, $a_n$ is the last term, and n is the number of terms

Here, we can say the first term occurs when n = 2:

-4 + 5n

-4 + 5 * 2 = -4 + 10 = 6

The last term will be when n = 10:

-4 + 5n

-4 + 5 * 10 = -4 + 50 = 46

The number of terms is just 10 - 2 + 1 = 9 terms.

Substitute these in:

$S=\frac{(a_1+a_n)*n}{2}$

$S=\frac{(6+46)*9}{2}=\frac{468}{2} =234$

Thus, the answer is 234.