Answer:
= - 1.5n - 6
Step-by-step explanation:
Given that the sequence is arithmetic with n th term ( explicit formula
= a₁ + (n - 1)d
where a₁ is the first term and d the common difference
Here a₁ = - 7.5 and d = - 9 - (- 7.5) = - 9 + 7.5 = - 1.5
= - 7.5 - 1.5(n - 1) = - 7.5 - 1.5n + 1.5 = - 1.5n - 6
Step-by-step explanation:
Answer:
12 in
Step-by-step explanation:
The area (A) of a trapezoid is calculated as
A =
h(b₁ + b₂ )
where h is the height and b₁, b₂ the parallel bases
Given h = 6, b₁ = 8 and A = 60 , then
× 6 × (8 + b₂ ) = 60 , that is
3(8 + b₂ ) = 60 ( divide both sides by 3 )
8 + b₂ = 20 ( subtract 8 from both sides )
b₂ = 12
The length of the second base is 12 inches
Given:
second term = 18
fifth term = 144
The nth term of a geometric sequence is:

Hence, we have:

Divide the expression for the fifth term by the expression for the second term:

Substituting the value of r into any of the expression:

Hence, the explicit rule for the sequence is: