In Fig. 9.27, ABCDE is a pentagon. A line through B parallel to AC meets DC produced at F. Show that:

(i) ar (ACB) = ar (ACF)


(ii) ar (AEDF) = ar (ABCDE)



(i) ΔACB and ΔACF lie on the same base AC and are between the same parallels AC and BF

Area (ΔACB) = Area (ΔACF)


(ii) It can be observed that:


Area (ΔACB) = Area (ΔACF)


Area (ΔACB) + Area (ACDE) = Area (ACF) + Area (ACDE)


Area (ABCDE) = Area (AEDF)


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