Exercise 18
1 . Consider the triangle ABC such that BAC ˆ � 20 , AC � 80 and BC � 30 .
( a ) Find the possible values of ˆ ABC .
( b ) If ˆ ABC is an obtuse angle , find ˆ ACB .
[ 4 ]
[ 2 ]
2 . Consider the triangle ABC such that BC � 20 , AC � 151 and ABC ˆ � 33 .
( a ) Find the possible values of BAC ˆ . [ 4 ]
( b ) Hence , find the possible values of AB . [ 3 ]
( c ) For the above two cases , write down the difference between the perimeters of the triangle ABC .
[ 1 ]
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3 . Consider the triangle ABC such that BAC ˆ � 18 , AC � 35 and BC � 2.7 .
( a ) Find the possible values of ˆ ABC .
( b ) Hence , find the area of the triangle if it is greater than 6 .
[ 4 ]
[ 3 ]
4 . Consider the triangle ABC such that BC � 37 , AC � 27 and ABC ˆ � 41 .
( a ) Find the possible values of ˆ BAC .
It is given that the perimeter of the triangle ABC is less than 84 .
[ 4 ]
( b ) ( i ) Write down an inequality of AB .
( ii ) Hence , find the perimeter of the triangle ABC . [ 4 ] www . seprodstore . com
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