To add and subtract rational expression with unlike denominators you can do it the following step.

Step in adding or subtracting rational expressions with unlike denominators.
[tex]6 \: \: \: \: \: \: \: \: \: \: \: \: \: \: 2[/tex]
[tex] \times {}^{2} - 4 \: \: \: \: \: \: \: \: \: \: \times {}^{2} - 5 \times + 6 [/tex]
1.factor the denominator of each fraction to help find the LCD.
[tex]6 \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: 2[/tex]
[tex] \times - 2 \times + 2 \: \: \: \: \: \: \: \times - 2 \times - 3[/tex]
2.find the least common denominator.
[tex] \times - 2 \times + 2 \times - 3[/tex]
3.Multiply each expression by its LCD.
[tex]6 \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: 2[/tex]
[tex] \times - 2 \times + 2 \: \: \: \: \: \: \: \: \: \times - 2 \times -3[/tex]
4.Write the simplified expression.
[tex]6 \times 3 - 2 \times + 2[/tex]
5.let the simplified expression as the numerator and the LCD as denominator of new fraction
[tex]6 \times - 18 - 2 \times - 4[/tex]
[tex] \times - 2 \times + 2 \times - 3[/tex]
6.Combine like terms and reduce the rational expression if you can in this case the rational expression cannot be simplified.
[tex]4 \times - 22[/tex]
[tex] \times - 2 \times + 2 \times - 3[/tex]
Write your previous solution here for comparison ​