Answer:
A
Step-by-step explanation:
49y² - x² ← is a difference of squares and factors in general as
a² - b² = (a - b)(a + b) , then
49y² - x²
= (7y)² - x²
= (7y - x )(7y + x) → A
Answer:
z=16
Step-by-step explanation:
10=z-6
10+6=z-6+6
16=z
Answer:
We just add numerators and rewrite denominator.
Adding unlike dominators:
We need to find the same denominators. You need to find the least common multiple (LCM) of the two denominators.
Step-by-step explanation:
You mean unlike denominators and like denominators.
Adding like dominators: We just add numerators and rewrite denominator :
Example : 
Adding unlike dominators:
We need to find the same denominators. You need to find the least common multiple (LCM) of the two denominators.
For example :

LCM for 5 and 4 is 20 : Now, divide by 5 and multiply by 1 for first fraction. 20 divide by 4 and multiply by 3 :

U can see the answer in the picture below