Applying the Binomial Theorem Practice Test

Use Pascal's Triangle (row 3: $1,3,3,1$) to expand $$(2x-3)^3.$$

What is the coefficient of $x^4 y^2$ in the expansion of $$(x + y)^6$$? (You may use Pascal's Triangle row 6: $1, 6, 15, 20, 15, 6, 1$.)