Question 1180069


We are given the value of {{{a}}} and {{{c}}}; 

{{{a}}} is the width of the ellipse and {{{c}}} is the focus of the ellipse

for an ellipse the equation to be used to find {{{b}}} or the length of the ellipse is:

{{{a^2 = b^2 + c^2}}}

substitute the values in the equation to solve for the missing variable:

{{{c=3}}}
{{{8}}} units is {{{2a}}}, therefore, {{{a = 4}}}

{{{4^2 = b^2 + 3^2}}}

solve for {{{b}}}:

{{{ b^2= 4^2 - 3^2}}}

{{{ b^2=16 - 9}}}

{{{b = sqrt(7 )}}} units

Therefore, the value of {{{b}}} is {{{ sqrt(7 )}}}units and your answer is 

d. {{{ sqrt(7 )}}} units