1. **Problem statement:** We have the system of equations:
$$y = 4x + 3$$
$$y - ax - b = 0$$
which can be rewritten as:
$$y = ax + b$$
where $a$ and $b$ are constants.
We want to find how many solutions (points of intersection) this system has for different values of $a$ and $b$.
2. **Formula and rules:** Two lines intersect where their $y$ values are equal:
$$4x + 3 = ax + b$$
Rearranging:
$$4x - ax = b - 3$$
$$x(4 - a) = b - 3$$
3. **Cases:**
- If $4 - a \neq 0$, then
$$x = \frac{b - 3}{4 - a}$$
This gives exactly one solution (one intersection point).
- If $4 - a = 0$, i.e., $a = 4$, then the equation becomes:
$$0 \cdot x = b - 3$$
which means:
- If $b - 3 = 0$, i.e., $b = 3$, then the two lines are identical ($y = 4x + 3$), so there are infinitely many solutions.
- If $b - 3 \neq 0$, i.e., $b \neq 3$, then there is no solution because the lines are parallel but distinct.
4. **Summary:**
- For $a \neq 4$, there is exactly one solution.
- For $a = 4$ and $b = 3$, there are infinitely many solutions.
- For $a = 4$ and $b \neq 3$, there are no solutions.
This completes the analysis of the number of solutions depending on $a$ and $b$.
Line Intersections 7Cb3B5
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