Explanation:
Given that:
3(4x + 1) - 4x + 3 = -18
Multiply the number outside of the brackets with numbers on LHS.
⇛12x + 3 - 4x + 3 = -18
Shift variables on LHS and constant on RHS, changing it's sign
⇛12x - 4x = - 18 - 3 - 3
Subtract the values on LHS and RHS.
⇛8x = - 18 - 6
⇛8x = -24
Shift the number 8 from LHS to RHS.
⇛x = -24/8
Write the fraction in lowest form by cancelling method.
Therefore x = {-(24÷2)/(8÷2)}
= -12/4
= -3
Please let me know if you have any other questions.