Determine where the function is concave up and down. Answers in internal notation please

Consider the following function: () = - 2x + 15x2 - 36x + 5 Step 3 of 4: Determine where the function is concave up and concave down. Enter your answers in interval notation. Answer 3 Points Keypad Keyboard Shortcuts Separate multiple intervals with a comma. Selecting a radio button will replace the entered answer value(s) with the radio button value. If the radio button is not selected, the entered answer is used. Concave up on: Never concave up Prev Concave down on: Never concave down