Respuesta :

51894

Answer:

Step-by-step explanation:

triangle ABC is an equilateral so all angles and sides are equal to each other

AB = 6

triangle DEF is an isosceles so two of its angles are equal to each other

a triangles angles add up to 180°

to find the measure of these angles we’ll write this equation:

x + x + 40 = 180

and solve for x

2x + 40 = 180

2x = 140

x = 70°

so mF is 70°