Divide both sides by 2
2t/2 = 10/2
t=5
Answer: 13 3/4
Step-by-step explanation:
25 * 5 = 125
2 3/4 * 5 = 13 3/4
Answer:

Step-by-step explanation:
The diagonal of any square with side length
is equal to
. Since the side length of the square is 10, the diagonal must be
.
To support and prove this:
The diagonal creates two 45-45-90 triangles, with the diagonal being the hypotenuse of both of these triangles. The Pythagorean Theorem states that in any triangle, the sum of the squares of both legs is equal to the square of the hypotenuse (
).
Call the diagonal
. In these two triangles, both legs are equal to 10 (the side lengths of the square), and the hypotenuse is the diagonal. Thus, we have:

L = building side
W = non-building side
P = 2W + L = 42 (note only one L because the other L is the building itself)
Solve for L:
L = 42 - 2W
Area = l*w
Area = (42-2W)W = 42W - 2W2
Let area be y, so y = -2W2 +42W
Note this is a parabola pointing down because the coefficient of the W2 is negative. That makes the vertex the maximum for which we are searching.
Vertex of this parabola is at W=-b/2a, if the quadratic is aW2 + bW + c = 0
a = -2
b = 42
W = -42/(2*-2) = -42/-4 = 10.5
W = 10.5
L = 42-2(10.5) = 42-21 = 21
Area = L*W = 21 * 10.5
A = 220.5 ft2