Answer: The second matrix
If we want to write a proper matrix to represent the given system of equations, we have to arrange it in order:
[tex]a+b+c=180[/tex]
[tex]2a-b+0c=0[/tex]
[tex]4a+0b-c=-5[/tex]
After this, we can write the matrix with the coefficients of each equation:
[tex]\left[\begin{array}{ccc|c}1&1&1&180\\2&-1&0&0\\4&0&-1&-5\end{array}\right][/tex]
Being this, the matrix that represents the measure of each angle in Ming's triangle
