Question 393906
well you can't solve it unless it equals something ...
so im guessing that it equals 0
343-7(x+3)^2 = 0
1. subtract 343 from 0 
    -7(x+3)^2 = -343
2. divide both sides by -7
    (x+3)^2 = 49
3. the opposite of squaring, is square root, so root both sides
    x+3 = 7
4. subtract 3 from both sides
    x = 4