3 years ago

- If 2x2 + 8y = 121.5 and x2 - 8y = 121.5, then x = 9 6.36 16 7

Mathematics

1 answer:

Natalija [7]3 years ago

4 0

Step-by-step explanation:

2x² + 8y = 121.5

x² - 8y = 121.5

Add the equations together to eliminate the y terms.

3x² = 243

x² = 81

x = 9

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