∴a+3= 15-2a

3a= 12

a=4

2. The arithmetic square root of ∵b is 19.

So b= 19? =36 1

The square root of ∵ c is plus or minus 3.

∴c=9

2c= 18

So the original formula =36 1=a? + 18

Answer? =343

So a=7