If the determinant of the matrix (begin{pmatrix} 2 & x \ 3 & 5 end{pmatrix} = 13), find the value of x.
-
A.
-2 -
B.
-1 -
C.
1 -
D.
2
Correct Answer: Option B
Explanation
(begin{pmatrix} 2 & x \ 3 & 5 end{pmatrix} = 13)
(begin{vmatrix} 2 & x \ 3 & 5 end{vmatrix} = (2 times 5) – (3 times x) = 13)
(10 – 3x = 13 implies -3x = 3; x = -1)