The equation presented in the image is:

$4x + 3 = 15$

To solve this two-step equation:

Step 1: Isolate the variable term

We first need to subtract 3 from both sides to get rid of the constant on the left side:

$4x + 3 - 3 = 15 - 3$

This simplifies to:

$4x = 12$

Step 2: Solve for $x$

Now, divide both sides by 4 to isolate $x$:

$\frac{4x}{4} = \frac{12}{4}$

This simplifies to:

$x = 3$

So, the solution is $x = 3$.

Would you like further explanation on this? Here are some related questions for additional practice:

1. Solve: $5x + 4 = 24$
2. Solve: $7x - 5 = 30$
3. Solve: $2x + 8 = 18$
4. Solve: $6x - 9 = 15$
5. Solve: $3x + 7 = 22$

Tip: Always reverse the order of operations when solving equations, starting by undoing addition or subtraction, followed by multiplication or division.