Using trial and error
x^4+5x^2-36 factors to (x-2)(x+2)(x^2+9)
2x^2+9x-5 factors to (x+5)(2x-1)
so
(x-2)(x+2)(x^2+9)(x+5)(2x-1)=0
set each to zero
x-2=0
x=2
x+2=0
x=-2
x^2+9=0
x^2=-9
x=3√-1
x=3i
x+5=0
x=-5
2x-1=0
2x=1
x=1/2=0.5
roots are
x=-5-2,0.5,2, and the imaginary root 3i
The lid will have a base area of 55 1/4 square inches. The long sides of the lid will each have an area of 17 square inches. The short sides of the lid will each have an area of 13 square inches. The total surface area of the lid will be 115 1/4 square inches.
So, for the base, you have w = 6.5 and l = 8.5. Area = 6.5 * 8.5 = 55.25 = 55 1/4.
For the long sides, you have l = 8.5 and h = 2. Area = 8.5 * 2 = 17
For the short sides, you have w = 6.5 and h = 2. Area = 6.5 * 2 = 13
For the total surface area, you have one base which is 55.25, you have two long sides which are 2 * 17 = 34, and you have two short sides which are 2 * 13 = 26. 55.25 + 34 + 26 = 115.25 = 115 1/4.
Answer:
a) Arithmetic
b) 22.5
c) 4.5
d) a_n = 4.5 + 4.5(n - 1)
e) a_15 = 67.5
Step-by-step explanation:
a) Subtract one term by the term right before it, and the difference will be the common difference.
9 - 4.5 = 4.5
13.5 - 9 = 4.5
18 - 13.5 = 4.5
Therefore, the common difference is 4.5.
b) Since the common difference is 4.5, add 4.5 to the 18 (which was the last value given). The result is 22.5.
c) We have already figured out that the common difference is 4.5.
d) The explicit formula would be a_n = a1 + d(n - 1). The first term is 4.5 and d is also 4.5, so the explicit formula is a_n = 4.5 + 4.5(n-1).
e) Plug 15 into our explicit formula for n. a_15 = 4.5 + 4.5(14). The result is 67.5.
I think it is the second one but im not for sure
I hope that helped you
C
If you plug in the values in that equation, it works.
