If $\begin{bmatrix} a+b & 2\\5 & ab\end{bmatrix}=\begin{bmatrix}6&2 \\5&8\end{bmatrix}$ Then one set of values of a and b is :
Answer & explanation
Correct answer: option 1
The correct answer is Option (1) → 4, 2
$\begin{bmatrix} a+b & 2\\5 & ab\end{bmatrix}=\begin{bmatrix}6&2 \\5&8\end{bmatrix}$
$⇒a+b=6$ ...(1)
$⇒ab=8$ ...(2)
from (1) and (2),
$\frac{8}{b}+b=6$
$8+b^2=6b$
$b^2-6b+8=0$
$(b-4)(b-2)=0$
$b=4\,or\,2$
$a=2\,or\,4$