10=1+9 1x9=9
=2+8 2x8=16
=3+7 3x7=21
=4+6 4x6=24
=5+5 5x5=25
↑ Left: the possible measurements of the two fences, Right: the possible areas
out of the areas calculated, 25 sq feet is the maximum. :)
Ans: 25 square feet
Given:
square shape
Perimeter 28 feet
Find its area
A square has 4 equal sides, so perimeter is 4a
Perimeter = 4a
28 ft = 4 a
28 ft / 4 = a
7 = a
One side of the the square is 7 ft.
Area of a square is the measure of one side raised to the power of 2.
A = a²
A = (7 ft)²
A = 49 ft²
Combine the two equations in the right amounts to eliminate y :
-2 (2x + 3y) + (3x + 6y) = -2 (17) + 30
-4x - 6y + 3x + 6y = -34 + 30
-x = -4
x = 4
Solve for y :
2x + 3y = 17
8 + 3y = 17
3y = 9
y = 3
