Determine Horizontal Asymptote

• Factor out the highest power of x

• When that highest power approaches infinity, what is the value of the equation (any fraction with x, x², etc in denominator goes to 0)

EXAMPLE

• What is the horizontal asymptote of y = (4x + 3) / (3x + 5)

The highest power of x is 1 so divide everything by x

y = (4x/x + 3/x) / (3x/x + 5/x)

As x approaches infinity, 3/x = 0 & 5/x = 0, 3x/ x = 1, 4x/x = 4

y = (4 + 0) / (3 + 0) = 4/3