Answer:
<u>a(n)=80*(9/10)^(n-1)</u>
Step-by-step explanation:
I think u r confused
this sequence is geometric not arithmetic
HOw we know that ??
when we get a common difference <u>that must Be equal </u>
d=72-80=-8 not equal to d=64.8-72=-7.2
So it is not arithmetic
but when we get the common ratio that also must <u>be equal </u>
r=72/80=9/10 equal to r=64.8/72=9/10
So it is geometric
By using this equation:
a(n)=a*r^(n-1)
and we have <u>a=80 , r=9/10</u>
Then <u>a(n)=80*(9/10)^(n-1)</u>
<em>I really hope this helps <3</em>
Answer:
Step-by-step explanation:
A 36% discount means the selling price is (100-36)% = 64% of the original price.
$272 = 64% of x = 0.64·x
x = $272/0.64 = $425
Y = -(1/2)(x-2)² +8
Re write it in standard form:
(y-8) = -1/2(x-2)² ↔ (y-k) = a(x-h)²
This parabola open downward (a = -1/2 <0), with a maximum shown in vertex
The vertex is (h , k) → Vertex(2 , 8)
focus(h, k +c )
a = 1/4c → -1/2 = 1/4c → c = -1/2, hence focus(2, 8-1/2) →focus(2,15/2)
Latus rectum: y-value = 15/2
Replace in the equation y with 15/2→→15/2 = -1/2(x-2)² + 8
Or -1/2(x-2)² +8 -15/2 = 0
Solving this quadratic equation gives x' = 3 and x" = 2, then
Latus rectum = 5
Answer:
1
Step-by-step explanation:
if there is just k, the number behind it is always 1
