Given #A=((-1, 2), (3, 4))# and #B=((-4, 3), (5, -2))#, how do you find 3A? Precalculus Matrix Algebra Multiplication of Matrices 1 Answer Alan P. Apr 28, 2016 #3A=((-3,6),(9,12))# Explanation: If #k# is a constant and #M=((m_(11),...,m_(c1)),(...,...,...),(m_(r1),...,m_(rc)))# is a matrix then #color(white)("XXX")k*M=((k*m_(11),...,k*m_(c1)),(...,...,...),(k*m_(r1),...,k*m_(rc)))# Answer link Related questions What is multiplication of matrices? How do I do multiplication of matrices? What is scalar multiplication of matrices? What are some sample matrix multiplication problems? How do I multiply the matrix #((6, 4, 24),(1, -9, 8))# by 4? How do I multiply the matrix #((3, 0, -19),(0, 7, 1), (1, 1/5, 2/3))# by -6? How do I multiply the matrix #((6, 4, 24),(1, -9, 8))# by the matrix #((1, 5, 0), (3, -6, 2))#? Is matrix multiplication associative? If #A=((-4, 5),(3, 2))# and #B=((-6, 2), (1/2, 3/4))#, what is #AB#? In matrix multiplication, does ABC=ACB? See all questions in Multiplication of Matrices Impact of this question 2067 views around the world You can reuse this answer Creative Commons License