X - the score he must get

He must get at least 92 points.
Answer: 26
Step-by-step explanation:
lets replace a and b with the numbers provided
2+4(2+4)=2+4(6)=2+24=26
Finding the square<span> root of a </span>number<span> is the inverse operation of squaring that </span>number<span>. Remember, the </span>square<span> of a </span>number<span> is that </span>number<span> times itself. The perfect squares are the squares of the whole </span>numbers<span>. The </span>square<span> root of a </span>number<span>, n, written below is the </span>number<span> that gives n when multiplied by itself.
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SOLUTION
We have been given the equation of the decay as

So we are looking for the time
Plugging the values into the equation, we have

Taking Ln of both sides, we have

Hence the answer is 4308 to the nearest year