∵ x1+x2=1 [韦达定理] x1²=x1+9 ；x2²=x2+9 [x1 ,x2 满足方程]
∴原式=x1(x1²)+7(x2+9)+3x2-66
=(1-x2)(x1+9)+7x2+63+3x2-66
=(1-x2)(1-x2+9)+10x2-3
=10-x2-10x2+x2²+10x2-3
=-x2+(x2+9)+7
=16