Answer:
Equation=$140+$85=$225
Step-by-step explanation:
If she sold her bike for $140 less than she paid for it, and she sold it for $85, you add 140 to 85 to get out much she paid for. To check your answer do 225-140=85.
Answer:
-3k + 10
Step-by-step explanation:
-3k - (-8) + 2
-3k + 8 + 2 !!
-3k + 10 → simplified version of the given expression
!! → We got rid of the parenthesis by combining the two negative signs. The rules state that any 2 identical signs combined (in this case, - and -) equal a positive sign (+).
Hope it helped,
BiologiaMagister
Answer:
Check the explanation
Step-by-step explanation:
Kindly check the attached image below to see the step by step explanation to the question above.
<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
So what you have to do to figure this out is 47-20 to get 27, then take 27 and divide it by 3 to get the answer of 9 comic books were sold by John.