Math
posted by chchch .
Need help with domain and range
how do you find the domain and range of
y=x+8.
after that one how do you find the domain and range of 7x+y=1

the domain of all polynomials is all real numbers
the range of all linear equations (with nonzero slope) is all real numbers.
Think about it. You have a straight line that extends all the way in both directions. Assuming it is not horizontal, then there is no value for either x or y that does not have a point on the line. 
but how do you know if an equation is a straight line or not