Using the information given, name the right angles in each part of Fig. 2.40:

(a) BA BD


(b) RT ST


(c) AC BD


(d) RS RW


(e) AC BD


(f) AE CE


(g) AC CD


(h) OP AB


Fig. 2.40

A right angle is an angle of measure 90°. It is formed by two perpendicular lines.

(a) ABD because BA BD


(b) RTS because RT ST


(c) ACD and ACB because AC BD


(d) RTW and RTS because RT SW


(e) AED, AEB, BEC and DEC because AC BD and E is their point of intersection.


(f) AEC because AE CE


(g) ACD because AC CD


(h) AKO, AKP, BKO and BKP because OP AB and K is their point of intersection.


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