Question

What is the missing y-coordinate that would produce a slope of 3, if a line were drawn through the points left-parenthesis 4 comma 5 right-parenthesis and left-parenthesis 8 comma y right-parenthesis?

Answer 1

Since the slope of a line is
`(y_(2)-y_(1) )/( x_(2)-x_(1) )`
And 2 points of the line are given, (4,5) and (8,y) we can substitute those values into our equation.


`(y-5)/(8-4) = (y-5)/(4)`

Since the slope of the line is 3,

`(y-5)/(4) = 3`
Multiplying both sides by 4 would give us:

y-5=12
y=17

Therefore the missing y value equals 17.