12+3x=2x
12=-x
-12=x
the number is negitive 12
The answer is To this question is D

As we know :
Length of arc = Radius × Angle made by Arc at center [ in radians ]



or

A solution of salt and water contain 75 grams of water per 150 millimeters of the solution. If 1 mole of water weight 16 grams, how many moles of water would be present in 30 mil liter of the solution.
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