A=20 m2, b=_________, h=4m

To find the missing value of "b" in this scenario, we first need to understand the given information. In the equation provided, "A" represents the area, with a value of 20 m^2. "h" represents the height, with a value of 4m. And "b" represents the base, which we are trying to find.

To find the value of "b," we can use the formula for the area of a triangle, which is A = (1/2) * b * h. Rearranging this formula to solve for "b," we get:

b = (2 * A) / h

Plugging in the values we have, we can calculate the value of "b" as follows:

b = (2 * 20 m^2) / 4m
= 40 m^2 / 4m
= 10 m

Therefore, the missing value of "b" in this scenario is 10 meters.