On a number line -7 and -17 are marked. The position of -17 is
None of these
To the right or left of -7
To the right of -7
To the left of -7
The points A(5, -1, 1); B(7, -4, 7); C(1, -6, 10) and D(-1, -3, 4) are vertices of a [RPET 2000]
Find the area of the quadrilateral ABCD whose vertices are respectively A (1, 1), B (7, –3) C (12, 2) and D (7,21). [4 MARKS]