Question 940542
M is the matrix 

{{{M=(matrix(2,2,3,4,p,q))}}}


If {{{M}}} is a singular matrix and {{{p=2}}},calculate the value of {{{q}}}:

A square matrix which does not have an inverse. A matrix is {{{singular}}} {{{if}}} and {{{only}}} {{{if}}} its {{{determinant}}} is {{{zero}}}.

so,  {{{D=3q-4p=0}}}

substitute {{{p=2}}}

{{{3q-4*2=0}}}
{{{3q-8=0}}}
{{{3q=8}}}
{{{q=8/3}}}

check:

*[invoke determinant_of_2x2_matrix 3, 4, 2, "8/3"]