You are multiplying 2 to each term each time.
-40 is the 4th term
-40 x 2 = -80
-80 x 2 = - 160
-160 x 2 = -320
-320 x 2 = -640
-640 x 2 = -1280
-1280 x 2 = -2560
-2560 x 2 = -5120
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-5120 is your 11th term.
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hope this helps
Answer:
perimeter of rectangle= 2(4+X)
32=8+2x
32-8=2x
26=2x
26/2=X
14=X
perimeter of triangle=3×sides
20=3x
20/3=X
6.66=x
