3.
The answers 2 and 4 are incorrect because inserting that ad the missing exponent would create only a trinomial.
-9 is incorrect as it would create something more than a polynomial. 7 is incorrect as, if doing a certain type of division, would result in a larger polynomial.
Hope this helps!
30-f+8f=30
30+7f=30
Move +30 to the right side. Sign changes from +30 to -30.
30-30+7f=30-30
7f=0
Divde by 7
7f/7=0/7
Cross out 7 and 7, divide by 7. Becomes 1*1*f=f
f=0
Answer: f=0
Answer:
the top one that's orange
