Final answer:
The correct sentence that combines the two ideas with an appositive phrase is 'Jupiter, the largest planet in our solar system, is named for the ruler of the gods in Roman mythology.'
Step-by-step explanation:
The sentence that combines the two provided sentences with an appositive phrase is: "Jupiter, the largest planet in our solar system, is named for the ruler of the gods in Roman mythology." In this sentence, the appositive phrase 'the largest planet in our solar system' provides additional information about Jupiter and is used to combine the two ideas into one sentence smoothly.