Skills Handbook - Solving and Writing Linear Equations - Exercises - Page 894: 12

$k=3$

We start with the given equation: $5k+2(k+1)=23$ We apply the distributive property to simplify the left side of the equation: $5k+2k+2=23$ We subtract $2$ from both sides of the equation and combine like terms: $$5k+2k+2-2=23-2$$$$7k=21$$ We divide by $7$ on each side of the equation: $$\frac{7k}{7}=\frac{21}{7}$$$$k=3$$