Answer:
Dimensions :
x (the longer side, only one side with fence ) = 90 ft
y ( the shorter side two sides with fence ) = 45 ft
Total fence used 45 * 2 + 90 = 180 ft
A(max) =
Step-by-step explanation: If a farmer has 180 ft of fencing to encloses a rectangular area with fence in three sides and the river on one side, the farmer surely wants to have a maximum enclosed area.
Lets call "x" one the longer side ( only one of the longer side of the rectangle will have fence, the other will be along the river and won´t need fence. "y" will be the shorter side
Then we have:
P = perimeter = 180 = 2y + x ⇒ y = ( 180 - x ) / 2 (1)
And A (r) = x * y
A(x) = x * ( 180 - x ) /2 ⇒ A(x) = (180/2) *x - x² / 2
Taking derivatives on both sides of the equation :
A´(x) = 90 - x
Then if A´(x) = 0 ⇒ 90 - x = 0 ⇒ x = 90 ft
and from : y = ( 180 - x ) / 2 ⇒ y = 90/2
y = 45 ft
And
A(max) = 90 * 45 = 4050 ft²
5(3)-3(-2)
15-(-6)=
15+6=21
a negative plus a negative is a positive so its 21
4(3)-3(-2)
12-(-6)
12+6=18
21+18=39
Answer: x ≈ 1.59688927, −1.60312387, −4.67045686, 4.69039614, 7.872914, −7.91513776, −10.89002194
Step-by-step explanation:
Solve for x by simplifying both sides of the equation, then isolating the variable.
Simplify 2*cosx*(2x+30°) + √3=0
Simplify each term.
Apply the distributive property.
- 2 cos
(
x
) (
2
x
) +
2 cos
(
x
) *
30
° +
√
3
=
0
- Multiply 2 by 2
- 4 cos
(
x
) x + 2 cos
(
x
) *30
°
+
√
3
=
0
- Multiply 30
°by 2
- 4
cos
(
x
) x + 60
cos
(
x
)
+
√
3
=
0
- Reorder factors in 4 cos ( x ) x + 60 cos ( x ) + √3
- 4xcos(x)+60cos(x)+√3=0
- Graph each side of the equation. The solution is the x-value of the point of intersection. x ≈ 1.59688927 , − 1.60312387 , − 4.67045686 , 4.69039614 , 7.872914 , − 7.91513776 , − 10.89002194
Answer:
just follow the rules
Step-by-step explanation:
Cramer's rule applies to the case where the coefficient determinant is nonzero. ... A simple example where all determinants vanish (equal zero) but the system is still incompatible is the 3×3 system x+y+z=1, x+y+z=2, x+y+z=3.
Write the system as a matrix equation. ...
Create the inverse of the coefficient matrix out of the matrix equation. ...
Multiply the inverse of the coefficient matrix in the front on both sides of the equation. ...
Cancel the matrix on the left and multiply the matrices on the right.
