Answer:
x= -1, y = 6, z = 3
Step-by-step explanation:
let me solve it with Gaussian Elimination
<h2>9.</h2><h3>Given</h3>
<h3>Find</h3>
- linear approximation to the volume when the radius increases 0.4 cm
<h3>Solution</h3>
The equation for volume of a sphere is
... V = (4/3)π·r³
Differentiating gives
... dV = 4π·r²·dr
Filling in the given numbers gives
... change in volume ≈ 4π·(15 cm)²·(0.4 cm)
... = 360π cm³ ≈ 1130.97 cm³ . . . . . . volume of layer 4mm thick
<h2>11.</h2><h3>Given</h3>
- an x by x by 2x cuboid with surface area 129.6 cm²
- rate of change of x is 0.01 cm/s
<h3>Find</h3>
<h3>Solution</h3>
The area is that of two cubes of dimension x joined together. The area of each such cube is 6x², but the two joined faces don't count in the external surface area. Thus the area of the cuboid is 10x².
The volume of the cuboid is that of two cubes joined, so is 2x³. Then the rate of change of volume is
... dV/dt = (d/dt)(2x³) = 6x²·dx/dt
We know x² = A/10, where A is the area of the cuboid, so the rate of change of volume is ...
... dV/dt = (6/10)A·dx/dt = 0.6·(129.6 cm²)(0.01 cm/s)
... dV/dt = 0.7776 cm³/s
Answer:
D) y=-1/2x+4
Step-by-step explanation:
D) y=-1/2x+4
In order to be parallel, it has to have the same slope (-1/2). Also, if you plug in (-2,5) for x and y, it does pass through those coordinates.
We need the cross product of the two vectors.
a x b
=<2,-2,-3> x <3,2,2>
=
i j k
2 -2 -3
3 2 2
=<-4+6, -(4+9), 4+6>
=<2,-13,10>
The second vector is obtained by reversing the direction, namely <-2,13,-10>
Thus the two vectors are <2,-13,10> and <-2,13,-10>.
Two workers earning 8 bucks an hour for 40hrs, well, that means each worker is making 8*40 or 320 bucks, now, is two workers, so 320+320 or 640 is the total cost then.
now, the revenue, sales income, is 2,000 bucks, how much is 640 off of?
well, if we take 2000 to be the 100%, what is 640 in percentage off of it?
solve for "x".
