Ms. Ingham took 21 pens from a drawer to distribute to the class. If 77 pens remain in the drawer, how many pens were originally in the drawer?

Solve the system by the elimination method. 3x - 2y - 7 = 0 5x + y - 3 = 0 to eliminate y, the lcm is 2. which of the following is the resulting equations? 1.3x - 2y - 7 = 0 5x + y - 3 = 0 2.3x - 2y - 7 = 0 -10x - 2y + 6 = 0 3.3x - 2y - 7 = 0 10x + 2y - 6 = 0

Anyone know? will mark brainliest if correct

If f(x)= sqrt4x+9+2, which inequality can be used to find the domain of f(x)?