Question

Solve the expression given by 3x + 9 = 33 for x.
(a) 8
(b) 3
(c) 2
(d) 5

Answer 1

Hint: We will solve the question using addition and subtraction in such a way so that we can eliminate one number from either side of the equation and get it to the other side of the equation. We can start by subtracting the term 9 on both sides.

Complete step-by-step solution -
Now, we will first consider the expression $3x + 9 = 33$.
We will subtract 9 from both sides of the equation. Therefore, we will get $3x + 9 – 9 = 33 – 9$.
Now, we will cancel + 9 and – 9 in this equation and also - 9 from 33 to get 24. This results into a new expression which is given by $3x = 24$.
Now we will divide both sides of the equation by number 3.
Thus, we get $\dfrac{3x}{3}=\dfrac{24}{3}$. Therefore, we get x = 8.
Therefore, we have reached the value of the equation $3x + 9 = 33$ given by 8.
Hence, the required value of equation $3x + 9 = 33$ is 8 and the correct option is (a).

Note: We can directly solve this question. For this, we will consider the equation 3x + 9 = 33 and we will place the number 9 to the right side of the equation. Thus, we get 3x = 33 – 9. This results into 3x = 24. And since, after multiplying 3 and 8 together we get 24. Thus, we directly get the required value of the equation 3x + 9 = 33 which is given by x = 8. Take care of minus and plus sign while solving the equation. That is if the minus sign is taken to either side then it will become a plus sign. Similarly, for plus signs taken to either side of the equation, we will change it into negative.