∠BDC=30, so ∠CBD + ∠BCD=180-30=150
ΔDBC is isosceles, so ∠CBD=∠BCD=half of 150=75
∠ABC=∠ABD-∠CBD=155-75=80
ΔABC is isosceles, so ∠ABC=∠ACB=80
∠BAC=180-80-80=20
Answer:
That'll help a lot of people in the future ^.^
Step-by-step explanation:
Did you miss a part of the question while typing?
The calculation should only have two steps.
30 = d/6.5
195 = d
surface are is basically the area of all the shapes in the prism, so :
(2 x area of the triangles on the sides) + area of upper rectangle + area of bottom rectangle + area of side rectangle
(2x((1/2) x 12 x 5)) + (13 x 10) + (12 x 10) + (10 x 5)
110/141
I hope this helps
have a great day
make sure you multiply by the reciprocal
