Multiply out and simplify (x+7)(x-3)

Using FOIL (First, Outside, Inside, Last), we get:F: x²O: -3xI: 7xL: -21Adding these together gives x² + (-3x) + 7x + (-21)Which is the same as x² - 3x + 7x - 21Which simplifies to x² + 4x - 21