Question 639086
If one of the parallel sides of a trapezoid (trapezium in the UK)
is 2.3 cm, the height is 15 cm and the area 600 sq.cm., what is
the length of the other parallel side?
<pre>
   A = {{{expr(1/2)(b[1]+b[2])h}}}

 600 = {{{expr(1/2)(2.3+b[2])(15)}}}

Multiply both sides by 2

1200 = (2.3 + b<sub>2</sub>)(15)

Divide both sides by 15

  80 = 2.3 + b<sub>2</sub>

Subtract 2.3 from both sides:

77.7 = b<sub>2</sub>

Answer: 77.7 cm

Edwin</pre>