It really depends on the specific function, and what you want to solve for.
There is no "height" of a rectangle, unless it's a rectangular prism. Do you mean the length? If you have the area of the rectangle, the equation should be:A= L x WPlug in the area and the length and solve for the width, or plug in the area the width of the rectangle, and solve for the length.
Decimals are simply a way to express numbers. There is nothing to solve!
In a rectangle: P = 2(L + W) and A = LW P = 2(L + W) (replace P with 20) 20 = 2(L + W) (solve for L; divide by 2 to both sides) 10 = L + W (subtract W to both sides ) 10 - W = L A = LW (substitute 10 - W for L) A = (10 - W)W A = 10W - W2
You take the formula for a rectangle, replace what you know, and solve for the remaining variable.
More information is needed to solve this problem
You can certainly express the radius as a function of its area, yes. If the area is known, you can solve the formula for the area of the circle to uniquely get the radius. (The quadratic equation has two solutions; you will of course choose the positive solution for the radius.)
For a rectangle, it is 2(l + w) l = length w = width
Add together the lengths of each of its sides.
you have to multiply the number by the top.
Write an equation for the perimeter, and solve it. Remember that the perimeter is the sum of all four sides.