Can 10 plus 9 equal 21?

What does 288 times 4 equal? What is the area triangle if the height is 6 inches and the base is 8 inches? What is 863.33 degrees Fahrenheit? Are alternate exterior angles on parallel lines ever supplementary? How many cm is 16inch? How do you input 5 numbers and out put the sum and print these numbers in the inverted order using array structure? What do you get when you subtract two negatives? What do we call our system of numeration that we use to designate numbers? What is the incident angle of a beam of light if the beam of light is reflected at an angle of 15 degrees from the normal? What 2 number times together to make 1? What is the standard notation for 3.2trillion? What is the answer of -9 x? How many 2ft x 2ft squares will it take to cover 168 square feet? How many 9's are there in a pack of cards? How many different three digit palindromes can you make using only the digits 1and 2? What is the equivalent ratio of 12 5? What cannot run although it has three feet? What is the greatest common divisor of 5 and 2? You are a four-digit number your digits do not repeat A three is not part of you your ones digit is 4 more than your hundreds digit your tens digit is odd The sum of your digits is 10 your thousands d? Largest seven digit number?