Find the sum of the geometric sequence series 20-10+5-5/2

= 12.5

Step-by-step explanation:

This is equivalent to  

20*(1 - 1/2 + 1/4 - 1/8 + ...)  

= 20*[(1 + 1/4 + 1/16 + ...) - (1/2)(1 + 1/4 + 1/18 + ...)]  

= 10*(1 + 1/4 + 1/16 + ...)  

= 10 * (4/3) = 40/3 or 13.333...

To check for a gross error, notice that 20 - 10 + 5 - 5/2 = 12.5, so we are certainly in the correct general range (suggesting that my answer is in fact correct).

sss (side, side, side)

sas (side, angle, side)

asa (angle, side, angle)

aas (angle, angle, side)

hl (hypotenuse, leg)

i am thinking c. sorry if im wrong .

step-by-step explanation: