15x+40=115
15x+40-40=115-40
15x=75
15/15 x=75/15
x= 5
The answer is plane because it is a two dimensional figure
#1. About 15.
5x3
#2. About 9
26/3=8 2/3
We know that
We can write an Arithmetic Sequence as a rule:
<span>an = a1 + d(n−1)</span>
where
<span>a1 = the first term
<span>d =the "common difference" between terms
in this problem
a1=15 a2=7 a3=-1 a4=-9 ..... an=-225
d=a2-a1
d=7-15-----> d=-8
</span></span>an = a1 + d(n−1)
for
an=-225
d=-8
a1=15
find n
-225=15+(-8)*(n-1)--> (n-1)=[-225-15]/-8----> n-1=30---> n=30+1---> n=31
the answer is31