Answer:
x = 15 ft
y = 15 ft
A(max) = 225 ft²
Step-by-step explanation:
Let call "x " and " y " sides of the rectangle x (side paralll to the northern boundary, then:
A(r) = x*y and 4*x + 2*2*y = 120 or 4*x + 4*y = 120
4*x + 4*y = 120 ⇒ x + y = 30 ⇒ y = 30 - x
Area of the garden as a function of x is:
A(x) = x* ( 30 - x ) ⇒ A(x) = 30*x - x²
Taking derivatives on both sides of the equation
A´(x) = 30 - 2*x
A´(x) = 0 ⇒ 30 - 2*x = 0
2*x = 30
x = 30/2
x = 15 ft
And y = ( 30 - x )
y = 15 ft
A(max) = 15*15
A(max) = 225 ft²
-6/7
Negative six over seven
Answer:
x=3/22 ; y=-9/44
Step-by-step explanation:
1/2x+1/3=4
=>1/2x=4-1/3
=>1/2x=(12-1)/3
=>1/2x=11/3
=>22x=3
=>x=3/22....(1)
then,
3x+2y
2y=-3 . (3/22)
y=-9/44
Step-by-step explanation:
communitive property
