What is 12 devided by 2 x (6-3)

Solve this system of equations. 12x − 18y = 27 4x − 6y = 10

An arc subtends a central angle measuring 7pi/4 radians what fraction of the circumference is this arc?

How many real-number solutions does the equation have? -4x^2 + 10x + 6 = 0 a. no solutions b. two solutions c. infinitely many solutions d. one solution