Question 1209164
<br>
{{{4x^2 + 5x^2 + 14x + 6x - 8x^2 + c}}}<br>
Combine like terms:<br>
{{{(4x^2+5x^2-8x^2)+(14x+6x)+c}}}
{{{x^2+20x+c}}}<br>
Using the pattern {{{(x+a)^2=x^2+2ax+a^2}}}, we have<br>
2ax = 20x
a = 10
c = a^2 = 100<br>
ANSWER: 100<br>