<p>Hi, I would really appreciate an explanation for #8 on P.840 in the blue book. Thanks.</p>
<p>substitute 2y in second equation with the first equation:</p>
<p>2x + (2x + z) + z = 20
4x + 2z = 20
2x + z = 10 (now you have the first equation)</p>
<p>10 = 2y
y=5</p>
<p>7 1980 at the Commonwealth Heads of State Meeting in New Delhi, India, to</p>