31. 31. 15+p+19+11p 33 17q-18q-13q^4-7q+12q^2+3q 35. 3g^2-g^2-19-4g^2+10g-15+16g 37. 9f^2-8f^3+14f 39. 15k+8k^2+18-7k+14k-19

31. $15+p+19+11p = 12p + 34$<br /><br />33. $17q-18q-13q^{4}-7q+12q^{2}+3q = -13q^{4} + 12q^{2} + 3q$<br /><br />35. $3g^{2}-g^{2}-19-4g^{2}+10g-15+16g = -2g^{2} + 26g - 34$<br /><br />37. $9f^{2}-8f^{3}+14f = -8f^{3} + 9f^{2} + 14f$<br /><br />39. $15k+8k^{2}+18-7k+14k-19 = 8k^{2} + 22k - 1$