What is the solution to x^2 + 6x + 7

Which linear equations have an infinite number of solutions? check all that apply.  (x  –  3/7)  =  2/7(3/2x  –  9/14)8(x  +  2)  =  5x  –  1412.3x  –  18  =  3(–6  +  4.1x)(6x  +  10)  =  7(x  –  2)4.2x  –  3.5  =  2.1 (5x  +  8)

What is the missing constant term in the perfect square that starts with x^2 -20x

Aright cylinder has a diameter of 8 m and a height of 6m. what is the volume of the cylinder