Since y = 4x + 3 is a line, it is continuous over the whole real number system. In other words, there are no asymptotes or holes in it. If you want to determine the range for that function, simply plug the x-value of 7 into the function to solve for y at that x-value. If x = 7, then y = 4(7) + 3 and y = 31. When x = 10, then y = 4(10) + 3 and y = 43. That gives us the range
{y | 31 ≤ y ≤ 43}. That reads "y such that y is greater than or equal to 31 and less than or equal to 43."
