Answer:
y = 13
Step-by-step explanation:
Calculate the distance d using the distance formula
d = √ (x₂ - x₁ )² + (y₂ - y₁ )²
with (x₁, y₁ ) = (- 2, 7) and (x₂, y₂ ) = (6, y)
d = [tex]\sqrt{(6+2)^2+(y-7)^2}[/tex], that is
d = [tex]\sqrt{8^2+(y-7)^2}[/tex] = 10
[tex]\sqrt{64+(y-7)^2}[/tex] = 10 ← square both sides
64 + (y - 7)² = 100 ( subtract 64 from both sides )
(y - 7)² = 36 ← take the square root of both sides
y - 7 = 6 ( add 7 to both sides )
y = 13