Answer:
height = 4 meters
h = 2A / ( a + b )
Explanation:
Let A represent the area of the trapezoid, h, the height a, the length of one base and b, the length of the other base
Area of a trapezoid, A = ( a + b)* h / 2
Now let's slot in the given values
A= 18 sq meters
a = 3 meters
b = 6 meters
we have;
18 = ( 3 + 6 ) * h /2
18 = 9 * h /2
Cross multiply
18*2 = 9h
36 = 9h
divide both sides by the coefficient of h (9)
4 = h
therefore, h = 4 meters
To solve for h without substituting
From A = ( a + b )* h /2
cross multiply
2*A = ( a + b )* h
divide both sides by ( a + b )
2A / ( a + b ) = h
therefore,
h = 2A / ( a + b )