Question

How to calculate part b and c of this question??

Answer 1

For part a, while you didn't ask about this particular part, the equation you should have found is
`3x+4y-5=0`.\

For part b, we are given that ∠M = 90°. Recall that perpendicular lines join at a right angle by definition, and that the slope of a perpendicular line is the negative reciprocal slope

`m_(perp)= (-1)/(m)`.
Using the slope from part a,
`m= (-3)/(4)`, so
`m_(perp)= (4)/(3)`.
We can write the equation of the line through M and N as
`y+4= (4)/(3)(x-7)`.
We are trying to fine the value p for which x is 16, so we substitute 16 into the equation we just found and solve for y (which is p).

`y+4= (4)/(3)(16-7)= 12-4=8=p`

`p=8`

For part c,
`y=p+6=14`.