Yes they are
Hope this helps
Unsure of what you mean by "y1."
If you wish to solve this eqn for y, do this:
-5y = - 3x + 20,
-3x + 20
y = ---------------- = (3/5)x - 4 (answer)
-5
AB = √(5-0)^2 + (4-0)^2 = √25+16 = √41
BC = √(0-5)^2 + (8-4)^2 = √25+16 = √41
CD = √(-5 - 0)^2 + (4-8)^2 = √25+16 = √41
AD = √(-5-0)^2 + (4-0)^2 = √25+16 = √41
All the sides are equal so it is either a square or a rhombus.
The distance from A to C on the x axis is: 8-0 = 8 units.
The distance from B to D on the Y axis is: 5 - - 5 = 10 units.
Because the two distances are not the same, it is not a square.
The answer is 4. AB=BC ; therefore, ABCD is a rhombus.
4 + 10 = 2 x 2 + 2 x 5 = 2 x (2 + 5)