Question 217173
To compute 3B, simply multiply <u>every</u> entry in the matrix B by 3. 


In other words, {{{3B=3*(matrix(2,2,-5,12,0,3))=(matrix(2,2,3(-5),3(12),3(0),3(3)))=(matrix(2,2,-15,36,0,9))}}}



So {{{3B=(matrix(2,2,-15,36,0,9))}}}