What's the formula for finding the height of the trapezoid

What's the formula for finding the height of the trapezoid

S ladder = (upper bottom + lower bottom) * height / 2
Height = 2S ladder / (upper bottom + lower bottom)

It is known that the area formula of trapezoid is s = 2 / A + B, which is multiplied by H
① Change the above formula into a known formula for s, a, B and H. ② if a: B: S = 2:3:4, find the value of H

H = 4 / 11, s = (A / 2 + b) H = 1 / 2 (a + 2b) h, when ABS ratio is 2:3:4, substituting h to get the solution

In the area formula of trapezoid s = 1 / 2 (a + b) h, we know that a = 3, H = 4, when B=___ S = 16

S = 1 / 2 (a + b) H
h=2s/(a+b)
=2*16/(3+4)
=32 / 7 (32 / 7)

It is known that the area formula of trapezoid is s = 1 / 2 [a + b] h, when a = 3, B = 6, H = 4?

Substituting a = 3, B = 6, H = 4
S = (a + b) H / 2
S=（3+6）×4/2=9×4/2=36/2=18
The answer is s = 18
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