Question

it is given that triangle ABC is congruent to triangle D E F and A b is equal to 4.6 CM angle b is equal to 60 degree and Angle A is equal to 50 degree then what is the length of DE and also the measurement of angle f

Answer 1

since ∆ABC is congruent to ∆DEF, AB=DE=4.6cm.


now, in ∆ABC,
angleA+angleB+angleC=180°[since the sum of the angles of a triangle is always 180°]
=>50°+60°+angleC=180°
=>angleC=180°-110°
=>angleC=70°


now, angleC=angleF[since, ABC is congruent to ∆DEF ]
therefore angleF =70°