Answer
whats the problem.
Step-by-step explanation:
Zero slope. When it is a straight line across its a zero slope and when it’s up and down its undefined.
Answer:
Step-by-step explanation:
4x − y = −11
2x + 3y = 5
lets multiply the second equation by -2 and add it to the first:
4x − y = −11
-4x - 6y = -10
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0 - 7y = -21
y = -21/-7
y = 3
now we substitute this result in the first equation to find x:
4x − y = −11
4x - 3 = -11
4x = -8
x = -8/4
x = 2
so the solution is y = 3 and x =2
4x − 9y = −21
−10y = −30
we solve for y
−10y = −30
y = -30/-10
y = 3
and substitute in the first equation:
4x − 9y = −21
4x − 9(3) = −21
4x - 27 = -21
4x = 6
x = 6/4 = 3/2
so the solution is x = 3/2 and y = 3
4x + 3y = 5
2y = −6
we solve for y:
2y = −6
y = -6/2
y = -3
we do substitute in the first equation:
4x + 3y = 5
4x + 3(-3) = 5
4x - 9 = 5
4x = 14
x = 14/4
x = 7/2
so the solution is x = 7/2 and y = -3
7x − 3y = −11
9x = −6
we solve for x:
9x = −6
x = -6/9
x = -2/3
then we substitute in the first equation the result found:
7x − 3y = −11
7(-2/3) − 3y = −11
-14/3 - 3y = -11
we multiply by 3 to eliminate fractions:
-14 - 9y = -33
9y = 19
y = 19/9
so the solution is x = -2/3 and y = 19/9
12x − 3y = −33
14x = −28
we solve for x:
14x = −28
x = -28/14
x = -2
then we substitute in the first equation:
12x − 3y = −33
12(-2) − 3y = −33
-24 - 3y = -33
3y = 9
y = 3
then the solution is x = -2 and y = 3
Answer:
Rectangular area as a function of x : A(x) = 200*x + 2*x²
A(max) = 5000 m²
Dimensions:
x = 50 m
l = 100 m
Step-by-step explanation:
"x" is the length of the perpendicular side to the wall of the rectangular area to be fenced, and we call "l" the other side (parallel to the wall of the barn) then:
A(r) = x* l and the perimeter of the rectangular shape is
P = 2*x + 2*l but we won´t use any fencing material along the wll of the barn therefore
P = 2*x + l ⇒ 200 = 2*x + l ⇒ l = 200 - 2*x (1)
And the rectangular area as a function of x is:
A(x) = x * ( 200 - 2*x) ⇒ A(x) = 200*x + 2*x²
Taking derivatives on both sides of the equation we get:
A´(x) = 200 - 4*x ⇒ A´= 0
Then 200 - 4*x = 0 ⇒ 4*x = 200 ⇒ x = 50 m
We find the l value, plugging the value of x in equation (1)
l = 200 - 2*x ⇒ l = 200 - 2*50 ⇒ l = 100 m
A(max) = 100*50
A(max) = 5000 m²
