Answer:
Values of [tex]a=-14.14,2.47[/tex]
Step-by-step explanation:
Let us find the determinant
[tex]a(-a-40)-2(a^2-48)+1(5a+6)=0\\\\-a^2-40a-2a^2+96+5a+6=0\\\\-3a^2-35a+105=0\\\\a=\frac{35\pm \sqrt{35^2-4\times -3\times 105}}{2\times -3}\\\\a=\frac{35\pm 49.84}{-6}\\\\a=\frac{35+ 49.84}{-6}=-14.14\\\\or\\\\a=\frac{35- 49.84}{-6}=2.47[/tex]
