If you change the sign of a point's x-coordinate, how does the location of the point change?

Amerchant has coffee worth $60 a pound that she wishes to mix with 50 pounds of coffee worth $90 a pound to get a mixture that she will sell for $70 a pound. how many pounds of the & 60 coffee should be used?

How to simply and write the answer n a whole number

Identify the initial amount a and the growth factor b in the exponential function. a(x)=680*4.3^x