John earns $180 per week plus $25 for each sale written an quality to represent how many sales he needs to make to earn at least $500?

In the field of thermodynamics, rankine is the unit used to measure temperature. one can convert temperature from celsius into rankine using the formula c= r/1.8 - 273, what is the temperature in celcius corresponding to r degrees rankine.

Is this a polynomial function? i need to know asap

X+ y = 5 ; x - y =3 solve using linear combination