12. Complete the coordinate proof.
Given: A(0, 6), B(6, 6), C(6, 0), D(0, 0); ZDAB, LABC, ZBCD, LCDA are right angles.
Prove: ABCD is a square.
A square on a coordinate plane
Proof:
• AB=√√(2₂-21)² + (92-3₁)² so AB =
•
BC= √(x2-₁)² + (32-3₁)² so BC =
CD=√(22-21)²+(3/2 - 3/₁)² so CD =
DA=√(22-21)²+(2-₁)²
so DA =
.
Since ABCD has four
angles and four
sides, it is a square.
