Answer:
1. All real numbers
2. All real numbers except y = 0
3. All real numbers except x = -7
4. All real numbers except b = 10
Step-by-step explanation:
For any function to be defined at a particular value, it should not be <em>approaching to a value </em>
<em> or it should not give us the </em>
<em> (zero by zero) form </em> when the input is given to the function.
The value of function will depend on the denominator.
Now, let us consider the given functions one by one:
1. 5y+2
Here denominator is 1. So, it can not attain a value
or
<em> (zero by zero) form </em>
So, for all real numbers, the function is defined.

At y = 0, the value

So, the given function is <em>defined for all real numbers except y = 0</em>
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Let us consider denominator:
x + 7 can be zero at a value x = -7

So, the given function is <em>defined for all real numbers except x = -7</em>
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
Let us consider denominator:
10-b can be zero at a value b = 10

So, the given function is <em>defined for all real numbers except b = 10</em>
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