Is 8 a solution to 1/2x+9=13? Explain

Yes 8 is a solution. this is because when replacing 8 with x on a calculator you do 1/2x8+9 and it will give you an answer of 13

Yes, because there is exactly one value of x.

first, you can add - 9 to both sides to cancel out the 9, which leaves you with the equation 1/2x = 4

then, simply divide both by 1/2 and you get 8.