the area of a circle is added to its diameter , and the circumference is then subtracted from this total , the result is 10 . what is the radius of the circle ?
the equation is ; diameter + area - circumference = d + a - c = d + pi * r ^ 2 - 2 * pi * r = 2 r + pi * r ( r - 2 ) . by plugging in the answers we can test the answers quickly ; then , 4 is the only possible answer . answer : e
sqrt(subtract(power(divide(multiply(subtract(const_1, const_pi), const_2), const_pi), const_2), multiply(const_4, negate(divide(10, const_pi)))))