Find a positive value of the given variable so that the trinomial is factorable.
-$13 y ^ { 2 } + b y - 1 ; b =$ ?
A) 12
B) 15
C) 14
D) 13

Question

Quizplus · Accepted Answer

The trinomial is factorable if $b^2+4(13)(-1)<0$. This simplifies to $b^2-52<0$. Factoring, we get $(b-2\sqrt{13})(b+2\sqrt{13})<0$. Therefore, $b$ must be between $-2\sqrt{13}$ and $2\sqrt{13}$. The only choice that satisfies this condition is $b=12$.

Find a Positive Value of the Given Variable So That 13y2+by−1;b=13 y ^ { 2 } + b y - 1 ; b =13y2+by−1;b=

Find a Positive Value of the Given Variable So That $13 y ^ { 2 } + b y - 1 ; b =$