It is a vector question?

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1 Answer
May 1, 2018

# p= 6.5 \ \ #, and #q= -1.5#,

Explanation:

We have:

# bbvec(OA) = ((0),(2),(-3)) \ \ #, # bbvec(OB) = ((2),(5),(-2)) \ \ # and # bbvec(OC) = ((3),(p),(q)) #

And so we can compute the vector # bbvec(AB) #,

# bbvec(AB) = bbvec(OB) - bbvec(OA) = ((2),(5),(-2)) - ((0),(2),(-3)) = ((2),(3),(1)) #

Similarly, we can compute the vector # bbvec(BC) #,

# bbvec(BC) = bbvec(OC) - bbvec(OB) = ((3),(p),(q)) - ((2),(5),(-2)) = ((1),(p-5),(q+2)) #

As ABC is a straight line then, for some constant #lamda#,

# bbvec(AB) = lamda bbvec(BC)#

Hence we have:

# ((2),(3),(1)) = lamda ((1),(p-5),(q+2)) #

Equating components:

# R1: 2 = lamda#,
# R2: 3=lamda(p-5) => p-5=3/2 => p= 6.5#,
# R3: 1=lamda(q+2) => q+2=1/2 => q= -1.5#,