Practicing Success
For what value of x will |A| =-4 if A = \(\begin{bmatrix}x & -x\\5 & x \end{bmatrix}\)? |
x=1 x=4 Both (a) and (b) None of these |
Both (a) and (b) |
|A| = -4 -4 = \( { x }^{ 2 } -5x\) \( { x }^{ 2 }- 5x\)+4 = 0 (x-1)(x-4) = 0 x=1 and x=4 |