Problema Solution

The vertices of a triangle are P(-12,1),Q(9,3), and R(11,-18).Prove that traingle PQR is a right triangle

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Answer provided by our tutors

distance between PQ = squrt(212+22) = sqrt(445)

distance between QR = sqrt(22+212) = sqrt(445)

distance between PR = sqrt(232+192) = sqrt(890)

now PQ2 + QR2 = 445 + 445 = 890 = PR2 hence right angled triangle