40 because 3+6+12 = 21 and 8+11+21 =40
It should take 4 years, please mark me brainliest it would mean a lot and if you want an explanation, Comment and I’ll help you out
L# = 1 + 3S#
8S# - 2L# = 10
8S# - 2(1 + 3S#) = 10
8S# - 2 + 6S# = 10
14S# = 12
S# = 6/7
L# = 1 + 3(12/14)
L# = 25/7
Since the formula to find the area of a parallelogram is base times height (A=bh), and you have been given the area and base already, you can set up an equation. Let h=height in this formula. h x 3.4 = 25. Using this formula, to find the height, you would divide 25 by 3.4 and get approximately 7.35 inches. So, your height= 7.35in. Hope this helps!