Find NM
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Answer:
[tex] MN= \boxed{15}[/tex]
Step-by-step explanation:
refer the attachment
therefore Let,
according to the question
[tex] \displaystyle (x - 3 ) (x + 13) =( x + 3 {)}^{2} [/tex]
simplify square and Multiplication:
[tex] \displaystyle {x}^{2} + 10x - 39 = {x}^{2} + 6x + 9[/tex]
cancel x² from both sides:
[tex] \displaystyle 10x - 39 = 6x + 9[/tex]
cancel 6x from both sides:
[tex] \displaystyle 4x - 39 = 9[/tex]
add 39 to both sides:
[tex] \displaystyle 4x = 48[/tex]
divide both sides by 4:
[tex] \displaystyle \boxed{x = 12}[/tex]
given that,
[tex] MN= x + 3[/tex]
substitute the got value of x:
[tex] MN= 12 + 3[/tex]
simplify addition hence,
[tex] MN= \boxed{15}[/tex]