Answer:

Step-by-step explanation:

Answer:
The largest possible volume V is ;
V = l^2 × h
V = 20^2 × 10 = 4000cm^3
Step-by-step explanation:
Given
Volume of a box = length × breadth × height= l×b×h
In this case the box have a square base. i.e l=b
Volume V = l^2 × h
The surface area of a square box
S = 2(lb+lh+bh)
S = 2(l^2 + lh + lh) since l=b
S = 2(l^2 + 2lh)
Given that the box is open top.
S = l^2 + 4lh
And Surface Area of the box is 1200cm^2
1200 = l^2 + 4lh ....1
Making h the subject of formula
h = (1200 - l^2)/4l .....2
Volume is given as
V = l^2 × h
V = l^2 ×(1200 - l^2)/4l
V = (1200l - l^3)/4
the maximum point is at dV/dl = 0
dV/dl = (1200 - 3l^2)/4
dV/dl = (1200 - 3l^2)/4 = 0
3l^2= 1200
l^2 = 1200/3 = 400
l = √400
I = 20cm
Since,
h = (1200 - l^2)/4l
h = (1200 - 20^2)/4×20
h = (800)/80
h = 10cm
The largest possible volume V is ;
V = l^2 × h
V = 20^2 × 10 = 4000cm^3
Multiply by a across the formula
5(2x-3)-(x+8)=13
10x-15-x-8=13
9x-23=13
9x=36
x=4
<span>The vertex of the parabola is the highest or lowest point of the graph.
</span><span>y=-4x^2+8x-12 = -4 (x^2 -2x +3)
Lets work with this now: </span>x^2 -2x +3
x^2 -2x +3 -> what is the closeset perfect square?
x^2 -2x +1 = (x-1)^2
So
x^2 -2x +3 = (x-1)^2 +2
Replacing to original
y=-4x^2+8x-12 = -4 (x^2 -2x +3) = -4 ((x-1)^2 +2) = -4 (x-1)^2 - 8
The min or max point is where the squared part = 0
So when x=1 , y= -4*0-8=-8
This will be the max of the parabola as there is - for the highest factor (-4x^2)
The max: x=1, y= -8