LMN is a right angled triangle with M being the right angle

LN=(√27+√12)

MN=(√18+√8)

Show that MN=5cm

Need a non calculator answer that explains it well because I don't really understand what to do.

Guest Mar 8, 2017

#2**0 **

Since it is a right triangle and LN is the hypotenuse: (your question asks for MN, but I suspect you meant ML)

ln^2 - mn^2 =ml^2

(sqrt27 + sqrt12)^2 - (sqrt18+sqrt8)^2 = ML^2 Do the math to find ML

(27+12 + 2 (sqrt(27x12)) - (18+8 + 2 sqrt(18x8)) = ML^2

(39+ 36) - (26+ 24) = ML^2

75-50= ML^2

25= ML^2

5 = ML

ElectricPavlov
Mar 8, 2017