Answer:
okay, we need to add up for all k=1 till k=22
we could do it like this
(-4*1 -13) + (-4*2 -13) + (-4*3 -13) + ...
but this is long and boring, so we need another valid, yet vastly faster method to calculate this sum
we know that the "-13" part will occur 22 times, so let's write this component as "-13*22"
the -4k gents bigger with each step, k will take all the natural numbers from 1 to 22
so we could write
"-4 * (1+2+3+4+5+6+7...+21+22l
alot simpler and faster, but not fast enough
let's add up all numbers from 1 to 22 into one number
1 + 22 = 23
2 + 21 = 23
3 + 20 = 23
...
this works eleven times (bc we use up 2 numbers in each step), so the numbers from 1 to 22 added up are just
23*11= 230+23 = 252
now let's construct the final calculation
-4 * 252 -13*22 = -1294
there's your sum.
hope it helps you overall.
brainliest would be very kind ic some else leaves an answer, may it be just a greeting
