Given:
Equilateral triangle: height = 2.6 inches ; base or side length = 3 inches
Rectangle: length = 6 inches ; width = 3 inches
1 name plate has 2 equilateral triangle and 3 rectangles.
Surface area of an equilateral triangle = √3/4 * a² = √3/4 * 3² = 3.9 in²
3.9 in² x 2 = 7.8 in²
Surface area of a rectangle = 6 in * 3 in = 18 in²
18 in² x 3 = 54 in²
7.8 in² + 54 in² = 61.8 in²
61.8 in² x 30 nameplates = 1,854 in² Choice A.
The answer is 6 or 8 which ever one u feel comfortable with
So to solve you need to set up equations, Using h as the height. So the base is 9 inches more (+9) than 3 times the height (3h) so 3h+9 equals the base. You have the area so you need to plug in the equation for the base and h for height and divide it all by 2. h(3h+9)/2=105. after you solve that and get h by itself you should get h= 7 and the b= 30