Question

Find the angle of the triangle formed by(-2,3)(3,8)(4,1)

Answer 1

we know that angle between two points is
cosA=[a1a2+b1b1/√(a²1+b²1)√(a²2+b²2)]
given A=(-2,3)
B=(3,8)
[-2*3+8*3/(√-2²+3²)(√3²+8²)]
[-6+24/√14*√73]
18/√14*√73
hope it helps u