2 times the sum of a number and 3 is equal to 3x plus 4 The phrase a number means an arbitrary variable, let's call it x. x The sum of a number and 3 means we add 3 to x: x + 3 2 times this sum means we multiply the quantity x + 3 by 2 2(x + 3) 3x plus 4 means 3x + 4 since the word plus means we use a (+) sign 3x + 4 The phrase is equal to means an equation, where we set 2(x + 3) equal to 3x + 4 2(x + 3) = 3x + 4