Question

Please help me find the missing coordinate (r)

Answer 1

r = 1

Explanation:

Calculate the slope m using the slope formula and equate to
`(1)/(2)`

m =
`(y_(2)-y_(1) )/(x_(2)-x_(1) )`

with (x₁, y₁ ) = (- 1, - 3) and (x₂, y₂ ) = (7, r)

m =
`(r+3)/(7+1)` =
`(r+3)/(8)` =
`(1)/(2)` ( cross- multiply )

2(r + 3) = 8 ← distribute left side

2r + 6 = 8 ( subtract 6 from both sides )

2r = 2 ( divide both sides by 2 )

r = 1