Just divide 78 with 11, 7.090909090909091.
Answer:
Step-by-step explanation:
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= 30°
Ok, use the sum of triangle theorm all angles of the triangle has a sum of 180 degrees. B is 90 degrees because it labeled it self ABC the A angle seems by the degree to be at the top of the triangle and there needs to be a 90 degree angle in a right triangle. Now if you add 90 + 28 you get 118 degrees subtract that from the sum of all the angles ( 180 degrees), and get 62 degrees as angle C. Angle A is 28 degrees, angle B is 90 degrees, angle C is 62 degrees.
Let, the width = w
We know, A = 2(lw + wh +hl )
250 = 2(10w + 5w + 50)
250 = 2(15w + 50)
250 = 30w + 100
30w = 250 - 100
w = 150/30
w = 5
In short, Your Answer would be Option C) 5 cm
Hope this helps!