Answer:

Step-by-step explanation:
Perimeter of the rhombus, STAR, is the sum of the length of all it's 4 sides.
The coordinates of its vertices are given as,
S(-1, 2)
T(2, 3)
A(3, 0)
R(0, -1)
Length of each side can be calculated using the distance formula given as 
Find the length of each side ST, TA, AR, RS, using the above formula by plugging in the coordinate values (x, y) of each vertices.

S(-1, 2) => (x1, y1)
T(2, 3) => (x2, y2)



T(2, 3) => (x1, y1)
A(3, 0) => (x2, y2)



A(3, 0) => (x1, y1)
R(0, -1) => (x2, y2)



R(0, -1) => (x1, y1)
S(-1, 2) => (x2, y2)



