# Cubes - diff

Second cubes edge is 2 cm longer than the edge of the first cube. Volume difference blocks is 728 cm3. Calculate the sizes of the edges of the two dice.

Result

a =  10 cm
b =  12 cm

#### Solution:

$(a+2)^3-a^3 = 728 \ \\ (a+2)(a^2+4a+4) -a^3 = 728 \ \\ 6a^2 + 12a +8 = 728 \ \\ a_{1,2} = \dfrac{ -q \pm \sqrt{ D } }{ 2p } = \dfrac{ -12 \pm \sqrt{ 17424 } }{ 12 } \ \\ a_{1,2} = \dfrac{ -12 \pm 132 }{ 12 } \ \\ a_{1,2} = -1 \pm 11 \ \\ a_{1} = 10 \ \\ a_{2} = -12 \ \\ a>0 \ \\ a = 10 \ \\ b = a+2 = 12$

Checkout calculation with our calculator of quadratic equations.

Our examples were largely sent or created by pupils and students themselves. Therefore, we would be pleased if you could send us any errors you found, spelling mistakes, or rephasing the example. Thank you!

Leave us a comment of this math problem and its solution (i.e. if it is still somewhat unclear...):

Be the first to comment!

Tips to related online calculators
Looking for help with calculating roots of a quadratic equation?
Tip: Our volume units converter will help you with the conversion of volume units.

## Next similar math problems:

1. Cube corners
The wooden cube with edge 64 cm was cut in 3 corners of cube with edge 4 cm. How many cubes of edge 4 cm can be even cut?
2. Gasoline canisters
35 liters of gasoline is to be divided into 4 canisters so that in the third canister will have 5 liters less than in the first canister, the fourth canister 10 liters more than the third canister and the second canister half of that in the first canist
3. Swimming pool
The pool shape of cuboid is 299 m3 full of water. Determine the dimensions of its bottom if water depth is 282 cm and one bottom dimension is 4.7 m greater than the second.
4. Combinations
How many elements can form six times more combinations fourth class than combination of the second class?
5. Variations 4/2
Determine the number of items when the count of variations of fourth class without repeating is 600 times larger than the count of variations of second class without repetition.
6. Equation
Equation ? has one root x1 = 8. Determine the coefficient b and the second root x2.
7. Cube corners
From cube of edge 14 cm cut off all vertices so that each cutting plane intersects the edges 1 cm from the nearest vertice. How many edges will have this body?
8. AS - sequence
What are the first ten members of the sequence if a11=22, d=2.
9. Volume of cube
Solve the volume of a cube with width 26cm .
10. Jar
From the cylinder shaped jar after tilting spilled water so that the bottom of the jar reaches the water level accurately into half of the base. Height of jar h = 7 cm and a jar diameter D is 12 cm. How to calculate how much water remains in the jar?
11. Theorem prove
We want to prove the sentence: If the natural number n is divisible by six, then n is divisible by three. From what assumption we started?
12. Discriminant
Determine the discriminant of the equation: ?
13. Roots
Determine the quadratic equation absolute coefficient q, that the equation has a real double root and the root x calculate: ?