Question

Please help! Correct answer only, please! I chose C as my answer on my first attempt, but it was incorrect. Determine the value of the following if it is possible. If it is not possible, explain. A. B. C. D.

Answer 1

Answer: C

Explanation:

To multiply a number (outside of a matrix), simply distribute that number to EVERY value of the matrix.

`X\left[\begin{array}{cc}a&b\\c&d\end{array}\right] \quad = \quad \left[\begin{array}{ccc}a(X)&b(X)\\c(X)&d(X)\end{array}\right] \\\\\\3\left[\begin{array}{cc}-2&0\\4&-7\end{array}\right] \quad =\quad \left[\begin{array}{cc}-2(3)&0(3)\\4(3)&-7(3)\end{array}\right]\quad = \quad \large\left[\begin{array}{cc}-6&0\\12&-21\end{array}\right]`