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If $6a^2 + 5a + 4 = 3,$ then what is the smallest possible value of $2a + 1$?

User Vivian
by
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1 Answer

6 votes

Answer: 0

Explanation:

The given equation:
6a^2+5a+4=3

Subtract 3 from both the sides, we get


6a^2+5a+1=0

Now , we can split 5a as 2a+3a and
2a* 3a = 6a^2

So,
6a^2+5a+1=0\Rightarrow\ 6a^2+2a+3a+1=0


\Rightarrow\ 2a(3a+1)+(3a+1)=0\\\\\Rightarrow\ (3a+1)(2a+1)=0\\\\\Rightarrow\ (3a+1)=0\text{ or }(2a+1)=0\\\\\Rightarrow\ a=-(1)/(3)\text{ or }a=-(1)/(2)

At
a=-(1)/(3)


2a+1=2(-(1)/(3))+1=-(2)/(3)+1=(-2+3)/(3)=\frac{1}3{}

At
a=-(1)/(2)


2a+1=2(-(1)/(2))+1=-1+1=0

Since,
0< (1)/(3)

Hence, the possible value of 2a+1 is 0.

User Morvael
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