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:
y=-4x-5
Step-by-step explanation:
The slope of the line is - 4, the equation of line is y=-4x-5
First of all, you would use the FOIL method for -5(a + 3). This means to just multiply -5 to all of the values in the parenthesis. This would equal:
-5a -15 = -55
Then after, you would add 15 for both sides and get -5a = -40
Divide by -5 on both sides, you get a = 8.
Here is a visual representation: https://puu.sh/zPxLC/a16740d0ce.png
Factoring f(x) would give a factor (x-1-2i), so you can divide f(x) by this, leaving (x-3)(x+4)(x-1+2i), so the other roots are:
x=3
x=-4
x=1-2i