Hey guys! what’s up :p

Evaluate the expression for the given value of the variable 2×(c2-5) for c=4

The school that imani goes to is selling tickets to the annual dance competition. on the first day of the ticket sales the school sold 7 adult tickets and 5 child tickets for a total of $96. the school took in $40 on the second day by seling 3 adult tickets . find the price of an adult ticket and the price of a child ticket. solve by using substitution elimination college prep algebra math heres the 2 equations i came up with 7x+5y=96 and 3x+2y= -40 show all workiv be stuck on this.

Find the center and the radius of the circle with the equation: x^2-2x+y^2+4y+1=0?