Question 1194390
Find the radius of a circle with an area of 100in^2 (using quadratic equations)
<pre>Quadratic equation formula? WHY?
Anyway, we get: {{{matrix(3,3, A, "=", pi*r^2, 100, "=", pi*r^2, pi*r^2 - 100, "=", 0)}}}

Quadratic equation formula: {{{matrix(1,3, r, "=", (- b +- sqrt(b^2 - 4ac))/(2a))}}}, where: {{{matrix(3,3, a, "=", pi, b, "=", 0, c, "=", 100)}}}

Should be pretty easy for you to substitute and calculate to find your answer, after IGNORING the negative value.</pre>