Sum of an infinite geometric sequence with the common ratio r, and the first term a1 is
we notice
-2 times -1/4=1/2,
1/2 times -1/4=-1/8
so a1=-2
r=-1/4 or -0.25
so the sum is
=
=
=
=
the sum is -8/5 or -1.6
Answer:
yes they form a proportion
The answer is 0 < x <span>≤ 7
</span>
First, we know that width = x
Which means that length = x +18
So, the possible equation for the Table's area is
X (X + 18) ≤ 175
X^2 + 18x - 175 <span>≤ </span>0
Next, we need to calculate is by using complete square method
x^2 + 18x + 81 <span>≤ 175 + 81
(x + 9)^2 </span><span>≤ 256
|x + 9| </span><span>≤ sqrt(256)
|x + 9| </span><span>≤ +-16
-16 </span>≤ x + 9 <span>≤ 16
</span>-16 - 9 ≤ x <span>≤ 16 - 9
</span>-25 ≤ x <span>≤ 7
Since the width couldn't be negative, we can change -25 with 0,
so it become
</span> 0 < x ≤ 7
-4/3x (or -1 1/3x if you use whole numbers instead of an improper fraction) -7 = 1
