L = 16 is the length W = 3 is the width H = q is the unknown height S = 362 is the surface area
We'll use the formula S = 2*(L*W+W*H+L*H) which is the surface area formula for any rectangular block
So plug in the given info and solve for q S = 2*(L*W+W*H+L*H) 362 = 2*(16*3+3*q+16*q) 362 = 2*(48+3q+16q) 362 = 2*(48+19q) 362/2 = 2*(48+19q)/2 ... divide both sides by 2 181 = 48+19q 48+19q = 181 19q+48 = 181 19q+48-48 = 181-48 .... subtract 48 from both sides 19q = 133 19q/19 = 133/19 .... divide both sides by 19 q = 7
