If you only want to simplify the problem, you would use the distributive property. 9k * 7k = 63[tex] k^{2} [/tex]. Then, 9k * 4 = 36k. However, if you wanted to solve for k, you would want to set the equation equal to 0. This gives you 63[tex] k^{2}[/tex] + 36k = 0. After factoring, k = 0 or -4/7.
