Question 914755
STEP 1: 

Find coefficient matrix (D), X matrix (Dx) and Y matrix (Dy). In this example we have.

D = {{{(matrix(2,2,
2,5,
1,1) )}}}

  

Dx={{{(matrix(2,2,
145,5,
50,1) )}}}



Dy={{{(matrix(2,2,
2,145,
1,50) )}}}


STEP 2:

 Find determinants for D, Dx and Dy.

det D= {{{(matrix(2,2,
2,5,
1,1) )}}}={{{2*1-5*1=-3}}}
           
det Dx= ={{{(matrix(2,2,
145,5,
50,1) )}}}={{{145*1-50*5=-105}}}


det Dy= ={{{(matrix(2,2,
2,145,
1,50) )}}}  ={{{2*50-1*145=-45}}}

STEP 3: 

Solve for the {{{x}}} and {{{y}}}

{{{x=D(x)/D=-105/-3=highlight(35)}}}

{{{y=D(y)/D=-45/-3=highlight(15)}}}