Answer:
[tex]KN\times~JN=LN\times~MN[/tex]
[tex](x-1)(x+20)=(x+11)(x+2)[/tex]
[tex]x^2+19x-20-x^2+13x+22[/tex]
[tex]7x=42[/tex]
[tex]x=6[/tex]
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hope it helps...
have a great day!!