Answer:
see explanation
Step-by-step explanation:
the sum to n terms of an arithmetic sequence is
=
[2a + (n - 1)d ]
where d is the common difference and a is the first term
here d = 9 - 7 = 7 - 5 = 2 and a = 5, hence
=
[(2 × 5) + 2(n - 1) ]
=
(10 + 2n - 2)
=
(2n + 8)
= n² + 4n
When sum = 165, then
n² + 4n = 165 ← rearrange into standard form
n² + 4n - 165 = 0 ← in standard form
(n + 15)(n - 11) = 0 ← in factored form
equate each factor to zero and solve for n
n + 15 = 0 ⇒ n = - 15
n - 11 = 0 ⇒ n = 11
but n > 0 ⇒ n = 11
Answer:
f(g(x)) = 2(x^2 + 2x)^2
f(g(x)) = 2x^4 + 8x^3 + 8x^2
Step-by-step explanation:
Given;
f(x) = 2x^2
g(x) = x^2 + 2x
To derive the expression for f(g(x)), we will substitute x in f(x) with g(x).
f(g(x)) = 2(g(x))^2
f(g(x)) = 2(x^2 + 2x)^2
Expanding the equation;
f(g(x)) = 2(x^2 + 2x)(x^2 + 2x)
f(g(x)) = 2(x^4 + 2x^3 + 2x^3 + 4x^2)
f(g(x)) = 2(x^4 + 4x^3 + 4x^2)
f(g(x)) = 2x^4 + 8x^3 + 8x^2
Hope this helps...
Answer:
Width = 18 inches
Length = 59 inches
Step-by-step explanation:
The length of a rectangle is five more than triple the width. If the perimeter is 154 inches, what are the dimensions
Perimeter of a rectangle = 2L + 2W
The length of a rectangle is five more than triple the width.
L = Length = 5 + 3W
W = Width
If the perimeter is 154 inches, what are the dimensions
Hence,
154 = 2L + 2W
154 = 2(5 + 3W ) + 2W
154 = 10 + 6W + 2W
Collect like terms
154 - 10 = 8W
144 = 8W
W = 144/8
W = 18 inches
Length = 5 + 3W
Length = 5 + 3(18)
Length = 5 + 54
Length = 59 inches
Answer:
The final answer is 16.
Gd luck with your work! :)