Solve for 'z'

Question

√(7z+1)=z+1

Answer 1

• 7z+1 = (z+1)²  ~ Square both sides
  
• 7z+1 = z²+2z+1 ~ Expand
• z²-5z=0 ~ Get everything to one side
• z(z-5)=0 ~ Factor
• z=0, 5

 

Now...because you squared the problem, get in the habit of checking both of your solutions, because many times you will get extraneous solutions that only work in the squared version, but not in the original square root problem.

 

In this case, both values do still work, so yes, z=0 or 5