X=20 distribute and combine like terms then divide
Two multiple choice questions, because: 3*28 is equal to 84, so if we do 8*2 we get 16, and 84+16 is 100! Hope this helped! Brainliest is always appreciated.
Answer:

Step-by-step explanation:
Foil the equation!
1. You see that is to the second power so it means this 
2. Then you use the Foil method. First, Outside, Inside, and Last.
3. Combined like terms
4. Answer!
A tip you can use to avoid Foil is this mental math trick: (Keep in mind this only works if the polynomial is being squared.)
1. Multiply the first number by itself = 
2. Add the first number by itself = 
3. Multiply the last number by itself = 
4. Combined to form your answer = 
NOTE: This is the same thing as a foil but it uses mental math so it takes less time!