Find the coordinates of points P, Q, R and S in Fig. 27.8.

Draw perpendiculars PA, QB, RC and SD from vertices P, Q, R and S on the x-axis. Also ,draw perpendiculars

PE, QF, RG and SH on the y-axis from these points.

PE = 10 units and  PA = 70 units

Therefore, the coordinates of vertex P are (10, 70).

QF = 12 units and  QB = 80 units

Therefore, the coordinates of vertex Q are (12, 80).

RG = 16 units and  RC = 100 units

Therefore, the coordinates of vertex R are (16, 100).

SH = 20 units and  SD = 120 units

Therefore, the coordinates of vertex S are (20, 120).