Best Answer

8 = 4*2

So 5*8 = 5*(4*2) which, by the associative property, = (5*4)*2

= 20*2

Can you do 20*2 more easily than 5*8?

If not, you need another round of associate property.

20 = 10*2

So 20*2 = (10*2)*2 = 10*(2*2) = 10*4

And if you cannot do 10*4 then this question is beyond you anyway and knowing 5*4 is not going to help.

Q: How does knowing that 5x4 equals 20 help you find 5x8?

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1x20 2x10 4x5

2X10 would work, as would 5X4.

no. 6x8 =48. 5x4 + 1x4 =20 + 4 =24.

20

5x4 - 2x = x*(5x3 - 2) and that cannot be factorised further without invoking surds.

Related questions

The answer is 20.

The Commutative Property (of Multiplication) says that 4x5 = 5x4. So, If 4x5 = 20, then 5x4 will also be 20.

1x20 2x10 4x5

2X10 would work, as would 5X4.

Associative property

no. 6x8 =48. 5x4 + 1x4 =20 + 4 =24.

No It is not 5x4=20 and 5x100=500

5x is a common factor of all terms:- 5x(x3+4x2+9)

5x4 meters = 20m2 = 215.28 square feet.

something like 5x4=4x5.

The lug pattern for 69 Dart is 5x4" original.

20