Question 959082
a) 4, same as the degree of the polynomial.
b,c) {{{x^4+25x^2 + 144 =(x^2+9)(x^2+16)=0}}}
{{{x^2+9=0}}}
{{{x=0 +- 3i}}}
and
{{{x^2+16=0}}}
{{{x=0 +- 4i}}}
d) Since the zeros are all complex, there are no x intercepts. The curve never crosses the x-axis.
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{{{graph(300,300,-2,2,-20,180,x^4+25x^2 + 144 )}}}