geometry - Coordinates of parallel triangle with a distance of 'd

I have a triangle with Co-ordinates $\{(x_1,y_1),(x_2,y_2),(x_3,y_3)\}$. I need to find co-ordinates of a triangle,whose edges are exactly $\alpha$ distance from previous triangle. Below is the fig

Median of Triangle: Definitions, Formula, Properties, Examples

geometry - Trilateration to know relative distance to a point. - Mathematics Stack Exchange

Distance between Two Parallel Lines and Solved Examples on the Distance between Two Parallel Lines

Calculating Distance formula Coordinate geometry – GeoGebra

Distance between Two Lines: Definition, Formula & Examples

mathematical optimization - Optimizing computation of distance to triangle using barycentric coordinates - Stack Overflow

Distance Formula - Derivation, Examples

GRE Geometry Formulas - Magoosh Blog — GRE® Test

Descriptive geometry . en point on the plane in which the axislies draw a line perpendicular to the axis.2. On this perpendicular lay off a point hav-ing its distance from the axis

Coordinate Geometry, Basic Introduction, Practice Problems

Dot Product - Distance between Point and a Line

Illustrative Mathematics

Lesson Explainer: The Perpendicular Distance between Points and Straight Lines in Space