Answer:
A = 1701,38 ft²
Dimensions :
x (north and south sides ) = 38.89 ft
y ( east and west sides ) = 43,75 ft
Step-by-step explanation:
North and south (sides of same length) equal "y" cost (4 + 5 ) = 4,5 $/ft²
East and west (sides of same length) equal "x" cost ( 3 + 5 ) = 4 $ /ft²
Equation of cost is
C = Cost of (north + south ) + Cost (east + west)
C = 2 * 4,5 * x + 4*2* y
C = 9x + 8y
700 = 9x + 8y ⇒ y = ( 700- 9x)/ 8
A = x*y
A(x) = x * ( 700 - 9x ) /8
A(x) = ( 700 x -9x²) / 8 A´(x) = ( 700 - 18 x )/ 8 A´(x) = 0
( 700 - 18 x )/ 8 = 0 ⇒ 700 - 18 x = 0 ⇒ x = 700/18
x = 38.89 ft
y = ( 700 - 9x )/8 ⇒ y = 349.99 / 8 ⇒ y = 43.75
And maximum ara is
A = x*y A = 38.89 * 43.75 = 1701,38 ft²
<h3>
Answer: 1.75 square feet</h3>
Work Shown:
area of the triangle on the left = base*height/2 = 0.75*2/2 = 0.75
area of the triangle on the right = base*height/2 = 0.5*4/2 = 1
total area = 0.75+1 = 1.75 square feet
