Answer:
i and iii
Step-by-step explanation:
First we find the common difference...to do this we subtract the first term from the second term. -7 - (-1) = -7 + 1 = -6
now we are going to find the 10th term
an = a1 + (n-1)*d <== formula for finding any term in arithmetic series
a1 = 1st term, d = common difference, n = term we want to find
now we sub
a10 = -1 + (10 -1) * -6
a10 = -1 + (9 * -6)
a10 = -1 - 54
a10 = - 55
now we will find the sum
Sn = (n (a1+ an)) / 2 <== formula for finding the sum
S10 = (10(-1 - 55))/2
S10 = (10(-56) / 2
S10 = -560/2
S10 = - 280
so the sum of the first 10 numbers is -280
Answer:
Width=20 feet
Since Length=Width=20 feet, the rectangle is a Square.
Step-by-step explanation:
Area,
To determine the width of the rectangle that gives the maximum area, we take the derivative of A and solve for its critical point.
The width of the rectangle that gives the maximum area =20 feet.
Perimeter of a rectangle=2(l+w)
Perimeter of the rectangle=80 feet
2(l+w)=80
2l+2(20)=80
2l=80-40
2l=40
l=20 feet
Since the length and width are equal, the special type of rectangle that produces this maximum area is a Square.
S = 2 (lw + lh + hw)
S = 2 ((8.5)(11) + (8.5)(2) + (11)(2))
S = 2 (93.5 + 17 + 22)
S = 2 (132.5)
S = 265 sq in
Answer:
2a
Step-by-step explanation:
2a(8+9b)
Open the bracket you have
16a+18ab