Add write the doubles fact you used to solve the problem 7+8=
+

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?

What number should be added to both sides of the equation to complete this square? x^2-10x=7

Which of these tools or constructions is used to inscribe a hexagon inside a circle?