Answer:
Answer: Sum of first 90 terms is Option d. 11655
Step-by-step explanation:
We have to find the sum of first 90 terms of the sequence -4,-1,2,5,8......
First we find the 90th term of the sequence
As we know the formula A(n)= A(1)+(n-1)d
Given from the sequence
A(1) = (-4)
n=90
d = 3
So A(n) = -4+(90-1)3
= (-4)+89×3
= 263
Now we know formula for the sum of any sequence is
Sum S(n) = 
Now we know n= 90
A(1) = -4
A(n) =263
Now we put the value in the formula
S(n)= 
= 45×259
= 11655
Answer:
=12b^6+6b³-18b²
Step-by-step explanation:
Area=length × width
A=3b²(4b⁴+2b-6)
=12b^6+6b³-18b²
Answer:
x =150 men
Step-by-step explanation:
Think of the total as workdays
125men* 120days = 15000 workdays
We still need 15000 workdays
100 days * x = 15000workdays
Divide by 100
x = 15000/ 100
x =150 men
Answer:
8cm
Step-by-step explanation:
Since the area of a square is Side X Side (s x s) it is also s². The s² is also equivalent = 64cm². To find the length of a side you do the √64cm² and you get 8cm for a side. Great Job!