Arrange the functions in ascending order, starting with the function that eventually has the least value and ending with the function that eventually has the greatest value.

The main factor when x values are high is the nature of the function. For example, polynomial functions intrinsically grow slower than exponential functions when x is high. Also, the greater the degree of the polynomial, the more the function grows in absolute value as x goes to very large values.

In specific, this means that our 2 exponential functions grow faster than all the other functions (which are polynomial) and thus they take up the last seats. Also, 7^x grows slower than 8^x because the base is lower. Hence, the last is 8^x+3, the second to last is 7^x.

Now, we have that a polynomial of 2nd degree curves upwards faster than a linear polynomial when x is large. Hence, we have that the two 2nd degree polynomials will be growing faster than the 2 linear ones and hence we get that they fill in the middle boxes. Because x^2+4>x^2, we have that x^2+4 is the 4th from the top and x^2 is the 3rd from the top.

Finally, we need to check which of the remaining functions is larger. Now, 5x+3 is larger than 5x, so it goes to the 2nd box. Now we are done.