First one simplifies to 2x + 6 = 2x + 7 which can't be true so this one has No Solution.
Same applies to the second equation ( 5x + 15 = 5x - 15) No solution
also the last one has no solution because it simplifies to 4x + 20 = 4x + 19
Im pretty sure its 18 unless im reading it wrong
If the length is 7/6 the width w then the perimeter is w + (7/6)w + w + (7/6w)
= 2((7/6)w + w) = 2w + (14/6)w = (26/6)w = (13/3)w.
So the answer is the last one.
Yes they are
Composite numbers <span />
Just compare it as a regular graph.:)