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
Answer:
Step-by-step explanation:
X^2-10x-8=0
Solve simultaneously
I will solve your system by substitution.<span><span>x=<span>−2</span></span>;<span>y=<span><span><span>23</span>x</span>+3</span></span></span>Step: Solve<span>x=<span>−2</span></span>for x:Step: Substitute<span>−2</span>forxin<span><span>y=<span><span><span>23</span>x</span>+3</span></span>:</span><span>y=<span><span><span>23</span>x</span>+3</span></span><span>y=<span><span><span>23</span><span>(<span>−2</span>)</span></span>+3</span></span><span>y=<span>53</span></span>(Simplify both sides of the equation)
Answer:<span><span>x=<span>−<span><span>2<span> and </span></span>y</span></span></span>=<span>5/3
<span>
so the answer is B (the second choice)
(Hope it helped ^_^)
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> -1 2/3 ÷ (-2 1/5)
> -1.66.. ÷ -2.2
> 0.75454...
Answer: 0.75
Now we have to,
find the required value of x.
Let's begin,
→ 3x-2 = 2(x-5)
→ 3x-2 = 2x-10
→ 3x-2x = -10+2
→ x = -8
Hence, value of x is -8.
