**Finding the Value of a Polynomial**
To find the value of a polynomial at a given value of x, we simply substitute that value into the polynomial and simplify the expression. In this case, we are given the polynomial 5x - 4x^2 + 3 and we need to find its value when x = 0.

**Substituting x = 0**
To substitute x = 0 into the polynomial, we replace every instance of x with 0 and simplify the expression.

Plugging in x = 0, we have:
5(0) - 4(0)^2 + 3

Simplifying the expression, we get:
0 - 4(0) + 3
0 + 0 + 3
3

Therefore, the value of the polynomial 5x - 4x^2 + 3 when x = 0 is 3.

**Locating Irrational Numbers on a Number Line**
To locate irrational numbers on a number line, we need to understand what irrational numbers are and how they differ from rational numbers.

**Rational Numbers**
Rational numbers are numbers that can be expressed as a ratio of two integers, where the denominator is not zero. They can be written in the form p/q, where p and q are integers and q is not equal to zero.

**Irrational Numbers**
Irrational numbers, on the other hand, cannot be expressed as a ratio of two integers. They cannot be written in the form p/q, where p and q are integers and q is not equal to zero. Irrational numbers are non-repeating and non-terminating decimals.

**Locating Irrational Numbers**
To locate irrational numbers on a number line, we can follow these steps:

1. Identify the irrational number or the range of irrational numbers that need to be located.
2. Choose a suitable scale for the number line, taking into account the magnitude of the irrational numbers.
3. Mark the rational numbers that are closest to the irrational numbers on the number line.
4. Estimate the position of the irrational numbers between the marked rational numbers.
5. If necessary, use a calculator or mathematical software to find the decimal representation of the irrational numbers for more accurate placement on the number line.

By following these steps, we can accurately locate irrational numbers on a number line.