Question

Please help me idk this

Answer 1

Answer:

$\large\boxed{Surface\ Area=63\ cm^2}$

Step-by-step explanation:

We have

square  with sides s = 3cm

four triangles with base b = 3cm and height h = 9cm.

The formula of an area of a square:

$A_\square=s^2$

The formula of an area of a triangle:

$A_\triangle=\dfrac{bh}{2}$

Substitute:

$A_\square=3^2=9\ cm^2\\\\A_\triangle=\dfrac{(3)(9)}{2}=\dfrac{27}{2}=13.5\ cm^2$

The Surface Area:

$S.A.=A_\square+4A_\triangle\\\\S.A.=9+4(13.5)=9+54=63\ cm^2$