The median of the trapezoid is the average of the bases. If we draw the trapezoid that is being described in this item, we will deduce that AB and DC are the bases and EF is given to be the median.
For this item,
EF = (AB + CD) / 2
Part A:
EF = (15 + 11) / 2 = 13
Part B:
AB = 2EF - CD
AB = (2)(14) - 10 = 18
Part C:
18 = ((5n - 9) + (2n + 3))/2
18 = (7n - 6) / 2
n = 6
Part D:
2y + 4 = ((5y + 2) + (-3y + 8))/2
y = 1
EF = 2(1) + 4 = 6
AB = (5(1) + 2 = 7
AB = -3(1) + 8 = 5
Method 1:
4(754)
=4(700+50+4)
=2800 + 200 + 16
=3000+16
=3016
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Method 2:
4(754)
=4(250+250+250+4)
=1000+1000+1000+16
=3016
, (49)^1/2 we can write it as square root of 49 , and also the square root of 49 is 7
-8.349562055 this is your answer