How To Calculate Surface Area?

Identify the shape of the surface (cube, rectangular prism, cylinder, sphere, cone, pyramid, etc.).

Determine the needed dimensions (e.g., side lengths, radius, height).

Use the correct surface-area formula for the shape:

Cube (side s): (6s^2)

Rectangular prism (length l, width w, height h): (2(lw + lh + wh))

Square pyramid (base side b, slant height s): (b^2 + 2bs)

Rectangular pyramid (base l×w, slant heights (s_1, s_2)): (lw + ls_1 + ws_2)

Cylinder (radius r, height h): (2pi r^2 + 2pi rh)

Cone (radius r, slant height s): (pi r^2 + pi rs)

Sphere (radius r): (4pi r^2)

Hemisphere (radius r): (3pi r^2) (curved only: (2pi r^2))

Triangular prism (triangle sides a, b, c; triangle area A; length L): (2A + L(a+b+c))

General composite surfaces: add the areas of all faces/sides and subtract overlapping/hidden areas if required

For slant height on pyramids/cones, compute from given dimensions when needed:

Right square pyramid: (s=sqrt{(b/2)^2+h^2})

Right circular cone: (s=sqrt{r^2+h^2})

Substitute values into the formula.

Use consistent units for all dimensions.

Evaluate and simplify the result.

If a problem requests rounding, round to the specified number of decimal places.

Report the final answer in square units (e.g., (text{cm}^2), (text{m}^2)).

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