X=4 x=-4 Due to the difference in squares theorem
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:
the correct answer is 302cm²
