Solve for x: 3x + 5 = 30 + 5.

Step-by-step solution

1. 1

   Simplify the right side before doing anything else. It is pure arithmetic:

   $30+5=35\qquad\Longrightarrow\qquad 3x+5=35$

   Missing that trailing $+5$ and solving $3x+5=30$ instead is the one real trap here, and it produces the wrong answer $\tfrac{25}{3}$.

2. 2

   Spot the shortcut. Both sides carry the same constant $+5$, so subtracting $5$ from each side removes it entirely — no fractions can arise:

   $3x=30$

3. 3

   Divide both sides by 3.

   $x=\frac{30}{3}=10$

   Because $30$ is a multiple of $3$, the answer is a whole number — another sign that the right side was read correctly.

4. 4

   Compare with the misread version. Had the equation truly been $3x+5=30$, the result would be $3x=25$ and $x=\tfrac{25}{3}\approx8.33$. The presence or absence of that final $+5$ is the whole difference between a clean integer and a fraction.

5. 5

   Verify in the original equation. Left: $3(10)+5=35$. Right: $30+5=35$ ✓. Both sides equal $35$, confirming $x=10$.