Does have an inverse? Why or why not?

A
A square matrix is invertible if its determinant is not zero.
The determinant for this matrix is
[tex]\begin{vmatrix}4&8\\7&14\end{vmatrix} = 4\cdot14 - 8\cdot7 = 56 - 56 = 0[/tex]
so it does not have an inverse because its determinant is zero.