Algebra 1

$(a^2+6a+5)/(2a+2) = (a+5)/2$ $(a+1)(a+5)/(2a+2) = (a+5)/2$ $(a+1)/(2a+2) = 1/2$ $(a+1)(1/2) = 1/2$ $a+1 = 1$ $a=0$ If $a = -1$, then the denominator is 0, and we can't have a number divided by zero.