Question

its urgent!! proper answer will be marked as brainliest....​

Answer 1

Answer:

a and b are integers such that b is the predecessor of a. Integers are the positive and negative whole numbers. If b is the predecessor of a, then b is a-1. For example, b=1, a=2 or b=-2, a=-1.

Step-by-step explanation:

I did not get the last one but This might be helpful to you . The value of a-b

Answer 2

Answer:

126

Step-by-step explanation:

8+3root7² - 8-3root7²/8-3root7 ×8+3root7

64+9×7-64+63/64-63

63+63/1 ;126