Question 815745
  <pre><font face = "Tohoma" size = 3 color = "indigo"><b> 
Hi,
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parallelogram has an area of 720 sq.cm. and a perimeter of 152 cm. 
one of the interior angles of the parallelogram is 30 degrees 
{{{sin 30 = (h/a) =  (1/2)}}} ,   h = a/2
 A = {{{bh = b(a/2) = 720cm^2}}}  b = 1440/a
 P = 2b + 2a = 152cm
0r   b + a = 76
    {{{1440/a + a = 76}}}
     a^2 - 76a + 1440 = 0
  (a-40)(a-36) = 0,  a = 40  0r  a = 36
Parallelogram is 40cm by 36cm

&#952;	radians	sin &#952;	cos &#952;	tan &#952;
0°	0	0	1	0
30°	&#960;/6	1/2	&#8730;3/2	&#8730;3/3
45°	&#960;/4	&#8730;2/2	&#8730;2/2	1
60°	&#960;/3	&#8730;3/2	1/2	&#8730;3
90°	&#960;/2	1	0	&#9472;