18. \( 0.7 c-10=0.5 \)

To solve the equation \( 0.7c - 10 = 0.5 \), you first want to isolate the variable \( c \). Start by adding 10 to both sides of the equation: \[ 0.7c = 0.5 + 10 \] This simplifies to: \[ 0.7c = 10.5 \] Next, divide both sides by 0.7 to solve for \( c \): \[ c = \frac{10.5}{0.7} \] Calculating that gives us: \[ c = 15 \] So, the solution to the equation is \( c = 15 \). 🎉 Now, here’s a tip: Always double-check your work by substituting the value back into the original equation. This way, you can confirm that both sides equal, ensuring you didn’t miss any simple errors along the way. Happy solving! 🤓