PLEASE HELP ASAP!!!!!!!
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Total amount of cardboard the designer will need is 62.5 square feet.
Solution:
Side length of the base = 5 ft
Area of the base = Side × Side
= 5 ft × 5 ft
Area of the base = 25 ft²
Area of a triangle [tex]=\frac{1}{2} \times5\times\frac{15}{4}[/tex]
= 9.375 ft²
Area of 4 triangle = 4 × 9.375
= 37.5 ft²
Total area of the shape = Area of the base + Area of 4 triangle
= 25 + 37.5
= 62.5 ft²
Total amount of cardboard the designer will need is 62.5 square feet.