The distance between the parallel planes ax + by + cz + d1 = 0 and ax + by + cz + d2 = 0 is d = |d1 − d2| a2 + b2 + c2 . find equations of the planes that are parallel to the plane x + 2y − 2z = −2 and two units away from it. (enter your answers as a comma-separated list of equations.)

Galen sold tickets of his church’s carnival for a total of $2,820. children’s tickets cost $3 each and adult tickets cost $5 each. the number of children’s tickets sold was 30 more than 3 times the number of adult tickets slod. how many children’s ticket and how many adult tickets did he sell?