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:
the total cost is $67
Step-by-step explanation:
9 × 3 = 27 8 × 5 = 40 40 + 27 = $67
To find the area of a rectangle, multiply its length by its width. I suggest you use a calculator for accuracy in multiplication. Hope this helped!
4) -0.3 = -1/3 < -1/7 since the bigger a negative number is the less positive it is. 1/8 is positive so it is clear that it should be placed last. & thus do all options this way.
5) B
Area of a triangle = ½ bh.
where b = base &
h = height.
Area of outer shape = (½ x 16 x 12) in^2.
= 96 in^2.
Area of unshaded inner shape = (½ x 3 x 4) in^2.
= 6 in^2.
Area of shaded region = (96 – 6) in^2.
= 90 in^2.
Answer:
They gave Americans confidence that victory over Britain was possible. You are welcome. :)
Step-by-step explanation: