Respuesta :

Answer: 7

Step-by-step explanation:

1. for Shawna's score to be opposite to Tim's score Shawna must score 25 (since 25 is the absolute or "opposite" of -25)

2. Shawna already has 18 points, and she needs 25...

[tex]18 +x = 25[/tex]

now we can easily solve this problem!

[tex]25 - 18 = x[/tex]

[tex]x = 7[/tex]

:D