the sum of the squares of three numbers is 138 , while the sum of their products take two at a time is 131 . find the sum ?
"formula is ( a + b + c ) ^ 2 = ( a ^ 2 ) + ( b ^ 2 ) + ( c ^ 2 ) + 2 ( ab + bc + ca ) = 138 + ( 2 * 131 ) the sum of the three numbers a + b + c = √ 400 = 20 answer is option c"
add(multiply(sqrt(divide(subtract(138, 131), const_2)), const_100), sqrt(subtract(138, divide(subtract(138, 131), const_2))))