which number should replace both the asterisks in ( * / 21 ) x ( * / 84 ) = 1 ?
"let ( y / 21 ) x ( y / 84 ) = 1 y ^ 2 = 21 x 84 = 21 x 21 x 4 y = ( 21 x 2 ) = 42 the answer is b ."
sqrt(multiply(84, 21))