Factor completely 3x2 − x − 4.
(3x − 1)(x + 4)
(3x + 4)(x − 1)
(3x − 2)(x + 2)
(3x − 4)(x + 1

 (3x − 4)(x + 1)

Step-by-step explanation:

Factoring is method to split an expression in simplest form.

Here the given expression is,

By middle term splitting,

Hence, fourth option is correct.

answer: b

step-by-step explanation:

ending amount = beginning amount / (2^n)

where "n" = number of half-lives (or elapsed time / half-life)

ending amount = 50 mg / (2 ^10 / 5.3)

ending amount = 50 mg / (2 ^ 1.8867924528)

ending amount = 50 m / 3.6981210597

ending amount = 13.5203794557 mg

or about 13.5 mg remain

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