Surface Area of a Rectangular Solid
<p><span style="font-size:22px"><a href="https://www.prepswift.com/quizzes/quiz/prepswift-surface-area-of-a-rectangular-solid" target="_blank">Surface Area of a Rectangular Solid Exercise</a></span></p><p>The <strong><span style="color:#8e44ad;">Surface Area of a Rectangular Solid</span></strong> is more annoying to calculate than the surface area of a cube, but, on the bright side, rectangular solids give us the opportunity to make pretty visuals.</p>
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<p>The area of the blue side is $xz$, the area of the pink side is $yz$, and the area of the yellow side is $xy$. But remember, <strong><u>we have two of each side</u></strong>! So the surface area formula is simply:</p>
<p><span style="font-size:22px;"><span style="color:#27ae60;">$$2xz + 2yz + 2xy = 2(xz + yz + xy)$$</span></span></p>
<p><strong><span style="color:#e74c3c;">Example</span></strong></p>
<p>What is the surface area of a rectangular solid that is $6$ inches wide, $11$ inches tall, and $4$ inches deep?</p>
<p>$$2(6 \times 11 + 6 \times 4 + 11 \times 4)$$</p>
<p>$$2(66 + 24 + 44)$$</p>
<p>$$2(134) = 268 \ in^2$$</p>