To solve this problem you must apply the proccedure shown below:
a) You must sum terms with same exponents, therefore, you have that the sum of these two polynomials is:
[tex] (x^{2}-4x+5)+(7x^{2}+2x-3) [/tex]
[tex] 8x^{2} -2x+2 [/tex]
b) First, you must mulitply the signs of the second polynomial by the negative sign, and them, you apply an algebraic sum. Therefore, the result is:
[tex] (7x^{2}+4x-6-2x^{2}+3x-1) \\ 5x^{2} +7x-7 [/tex]
The answers are: a)[tex] 8x^{2} -2x+2 [/tex]; b) [tex] 5x^{2} +7x-7 [/tex]
