Answer :

To add the given polynomials, we will combine the coefficients of terms with the same power of [tex]\(a\)[/tex]. Let's go through it step-by-step:

1. Identify the terms in each polynomial:

The first polynomial is:
[tex]\[ 9.7a^4 + 1 \][/tex]

The second polynomial is:
[tex]\[ -6.1a^4 - 7.3a^2 + 9.8 \][/tex]

2. Group the like terms:

We have terms involving [tex]\(a^4\)[/tex], [tex]\(a^2\)[/tex], and the constant terms (which are terms with [tex]\(a^0\)[/tex]).

- For [tex]\(a^4\)[/tex]:
[tex]\[ 9.7a^4 \text{ and } -6.1a^4 \][/tex]

- For [tex]\(a^2\)[/tex]:
[tex]\[ -7.3a^2 \text{ (from the second polynomial, there is no corresponding \(a^2\) term in the first polynomial)} \][/tex]

- Constant terms (terms with [tex]\(a^0\)[/tex]):
[tex]\[ 1 \text{ and } 9.8 \][/tex]

3. Add the coefficients of the like terms:

- Coefficient of [tex]\(a^4\)[/tex]:
[tex]\[ 9.7 + (-6.1) = 9.7 - 6.1 = 3.6 \][/tex]

- Coefficient of [tex]\(a^2\)[/tex]:
[tex]\[ -7.3 \text{ (no additional term to combine with)} \][/tex]

- Constant terms:
[tex]\[ 1 + 9.8 = 10.8 \][/tex]

4. Combine these results to form the new polynomial:

The resulting polynomial after combining the like terms is:
[tex]\[ 3.6a^4 - 7.3a^2 + 10.8 \][/tex]

Thus, the final sum of the polynomials [tex]\(\left(9.7a^4 + 1\right) + \left(-6.1a^4 - 7.3a^2 + 9.8\right)\)[/tex] is:

[tex]\[ 3.6a^4 - 7.3a^2 + 10.8 \][/tex]