Thirty times the square of a non-zero number is equal to 8 times the number. What is the number

1 answer:

7 0

X is the number
30(x²)=8x
minus 8 both sides
30x²-8x=0
factor out 30x
30x(x-8/30)=0
set each to zero

30x=0
x=0, nope, we said x can't be 0

x-8/30=0
x=8/30
x=4/15

the number is 4/15

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For a better understanding of the solution provided here please find the diagram in the attached file.

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This can be further simplified by dividing both the sides by the common factor 2 as:

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