Please help me idk this

Answer:
82.5
Step-by-step explanation:
I'm assuming you have to find the area of the triangle to find out how much cardboard she needs so you need the formula:
A =[tex]\frac{1}{2}[/tex]bh
A =[tex]\frac{1}{2}[/tex] 11 x 15
A =[tex]\frac{1}{2}[/tex] 165
A = 82.5
Sorry if its wrong