Answer:
<h2>-3400</h2>
Step-by-step explanation:
In general, a geometric sequence is given by:
<h3>
a,
ar,
ar^2,
⋯,
ar^n−1 </h3>
In the sequence 20, - 40 , 80,…
First term, a1 = 20
Common ratio, r = - 40 ÷ 20 = - 2
The nth term is = 9th
Sum of finite geometric series : Sn= ( a1 - a1r^n ) / ( 1 - r)
S9 = ( 20 - 20 x (- 2)^9 ) / ( 1 - ( - 2) )
S9 = ( 20 - 20 x - 512 ) / ( 1 + 2 )
S9 = ( 20 - 10240<em> </em>) / ( 3 )
S9 = ( - 10220 ) / 3
<h3>S9 = - 3400 <u>Answer</u> </h3><h2>Hope it's help you.... ^_^❤️</h2>
When the leading coefficient is 1,
If the constant ( c term) is a perfect square and the b term is 2* the square root of the c term.
Ex.
x*2 + 10x + 25
2*5 = 10 5*5=25
Ex.
x^2 - 12x + 36
2 * -6 = -12 6*6=36
15
Mark me brainliest! Hope it helps!!! :)
The answer to this question is 110
Answer:
B: 112.5
Step-by-step explanation:
first, we split up the rhombus into two triangles, with the height of 15 and the length of 7.5. when you multiply these you will get 112.5, and normally if you are just getting the area of the triangle, then you would divide it by two, but seeing that we have 2 triangles here, we would multiply it by two afterwards so an easier way to do it is just to not divide.
