Hello,
z=-2x²+15x-3y²+21y-6
=-2(x²-2*15/2*x+(15/2)²) -3(y²-2*7/2y+(7/2)²)-6+2*225/4+3*49/4
=-2(x-15/2)²-3(y-7/2)²+573/4
The max is for x-15/2=0 and y-7/2=0 thus 537/4
3 in the hundred-thousand place, 8 in thousands place, 4 in the hundreds place, 1 in the tens place, 2 in the one's place.
Answer:
z=16
Step-by-step explanation:
z/4-2=2(take l.c.m)
or,(z-8)/4=2
or,z-8=8
z=16
Answer:
The volume of the sphere is 14m³
Step-by-step explanation:
Given
Volume of the cylinder = 
Required
Volume of the sphere
Given that the volume of the cylinder is 21, the first step is to solve for the radius of the cylinder;
<em>Using the volume formula of a cylinder</em>
The formula goes thus

Substitute 21 for V; this gives

Divide both sides by h


The next step is to solve for the volume of the sphere using the following formula;

Divide both sides by r

Expand Expression

Substitute 



Multiply both sided by r

------ equation 1
From the question, we were given that the height of the cylinder and the sphere have equal value;
This implies that the height of the cylinder equals the diameter of the sphere. In other words
, where D represents diameter of the sphere
Recall that 
So, 

Substitute 2r for h in equation 1



Hence, the volume of the sphere is 14m³