Can someone solve this system of equations ?

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?

Josephine has a great garden with and area of 2x2 + x - 6 square feet

If a flying disk is 139 meters in the air and travels at an average of 13 m/s how long is it in the air