Answer :
x - tenths digit
y - units digit
[tex]10x+y=4(x+y)\\ 10x+y=2xy\\\\ 10x+y=4x+4y\\ 10x+y=2xy\\\\ 6x=3y\\ 10x+y=2xy\\\\ 3x=y\\ 10x+y=2xy\\\\ 10x+3x=2x\cdot3x\\ 13x=6x^2\\ 6x^2-12x=0\\ 6x(x-2)=0\\ x=0 \vee x=2\\\\ y=3\cdot2\\ y=6\\\\ 10\cdot2+6=\boxed{26}[/tex]
y - units digit
[tex]10x+y=4(x+y)\\ 10x+y=2xy\\\\ 10x+y=4x+4y\\ 10x+y=2xy\\\\ 6x=3y\\ 10x+y=2xy\\\\ 3x=y\\ 10x+y=2xy\\\\ 10x+3x=2x\cdot3x\\ 13x=6x^2\\ 6x^2-12x=0\\ 6x(x-2)=0\\ x=0 \vee x=2\\\\ y=3\cdot2\\ y=6\\\\ 10\cdot2+6=\boxed{26}[/tex]
