Solve the system of equations by substitution.

y= -x-2
3x+3y=6

Suppose a pendulum is l meters long. the time,t,in seconds that it tales to swing back and forth once is given by t=2.01

Average acceleration: i have no idea how to do this.

The rectangle shown has a perimeter of 108 cm and the given area. its length is 6 more than five times its width. write and solve a system of equations to find the dimensions of the rectangle.