Answer:
The rule of the arithmetic sequence is 13 - 2n
The 30th term is -47
Step-by-step explanation:
∵ f(n) = 11 and g(n) = -2(n - 1) = -2n + 2
∴ f(n) + g(n) = 11 + -2n + 2 = 13 - 2n
Use n = 1 , 2 , 3 , 4 to check the type of the sequence
∵ n = 1 ⇒ 13 - 2(1) = 11
∵ n = 2 ⇒ 13 - 2(2) = 13 - 4 = 9
∵ n = 3 ⇒ 13 - 2(3) = 13 - 6 = 7
∵ n = 4 ⇒ 13 - 2(4) = 13 - 8 = 5
∵ 11 , 9 , 7 , 5 is an arithmetic sequence with difference -2
∴ The rule of the arithmetic sequence is 13 - 2n
∴ The 30th term = 13 - 2(30) = -47
Answer:
-68 1/5
Step-by-step explanation:
Brainliest?
Comment
This is an area problem. The key words are 120 square feet and 12 feet longer.
And of course width is a key word when you are reading this.
Formula
Area = L * W
Givens
W = W
L = W + 12
Substitute and Solve
Area = L* W
120 = W*(W + 12)
W^2 + 12W = 120 square feet
w^2 + 12w - 120 = 0
This does not factor easily. I would have thought that a graph might help but not if the dimension has to be to the nearest 1/100 of a foot. The only thing we can do is use the quadratic formula.
a = 1
b = 12
c = - 120
w = [ -b +/- sqrt(b^2 - 4ac) ]/(2a)
w = [-12 +/- sqrt(12^2 - 4*(1)(-120)] / 2*1
w = [-12 +/- sqrt(144 - (-480)]/2
w = [-12 +/- sqrt(624)] / 2
w = [- 12 +/- 24.979992] / 2 The minus root has no meaning whatever.
w = (12.979992) / 2
w = 6.489995 I'll round all this when I get done
L = w + 12
L = 6.489995 + 12
L = 18.489995
check
Area = L * W
Area = 6.489995*18.489995
Area = 119.999935 The difference is a rounding error
Answer
L = 18.489995 = 18.49 feet
W = 6.489995 = 6.49 feet
Note: in the check if you round first to the answer, LW = 120.0001 when you find the area for the check. Kind of strange how that nearest 1/100th makes a difference.
Answer: 85
Step-by-step explanation: