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masuarezdl
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Statement Imasuarezdl wrote:In isoceles triangle RST what is the measure of angle R?
(1) The measure of angle T is 100deg.
(2) The measure of angle S is 40 deg.
Whats the logic behind this? I though both worked out alone sufficiently...
if angle T is 100 the other 2 angles are equal since the triangle is an isosceles triangle. Also angle T cannot be equal to another angle because then the sum of the 2 angles will be greater than 180
T + R+S = 180
100+2R = 180 [since R=S]
R = 40
Sufficient.
Statement II
Angle S = 40
angle S could be equal to angle T or angle R we don't know which of the 2 angles are equal.
Insufficient.
Hence A.
Hope this helps.
