Well, the box will have 7in long 4 in wide and 2 in high
u = 10.4 and v = 12
Solution:
In the given 2 sides of a triangle are 60°, 60°.
Sum of all the angles of a triangle = 180°
60° + 60° + third angle = 180°
⇒ third angle = 180° – 60° – 60°
⇒ third angle = 60°
All angles are equal, therefore the given triangle is an equilateral triangle.
⇒ All sides are equal in length.
⇒ v = 12
The line drawn from the top angle divides the triangle into two equal parts
and the line is perpendicular.
12 ÷ 2 = 6
Using Pythagoras theorem,

⇒ 
⇒ 
⇒ 
⇒ 
⇒ u = 10.4
Hence, u = 10.4 and v = 12.
F(x) = 9x² - 54x - 19 = 9x² - 57x + 3x - 19 = 3x(3x - 19) + 1(3x - 19)
= (3x - 19)(3x + 1)
f(x) = 0 if 3x - 19 =0 or 3x + 1 = 0
3x = 19 or 3x = -1
x = 19/3 or x = -1/3
Angle HDE is congruent to angle HFG