Question: find the set of value of $m$ which line $y=mx - 5$ does not intersect the curve $y=x^2 - 5x + 4$
1. **State the problem:**
Find the values of $m$ such that the line $y=mx - 5$ does not intersect the curve $y=x^2 - 5x + 4$.
2. **Set the equations equal to find intersection points:**
$$mx - 5 = x^2 - 5x + 4$$
3. **Rearrange to form a quadratic equation in $x$:**
$$x^2 - 5x + 4 - mx + 5 = 0$$
$$x^2 - (5 + m)x + 9 = 0$$
4. **Recall the condition for no intersection:**
The quadratic equation has no real solutions if its discriminant $\Delta < 0$.
5. **Calculate the discriminant:**
$$\Delta = b^2 - 4ac = (-(5 + m))^2 - 4 \times 1 \times 9 = (5 + m)^2 - 36$$
6. **Set the inequality for no real roots:**
$$(5 + m)^2 - 36 < 0$$
$$(5 + m)^2 < 36$$
7. **Solve the inequality:**
$$-6 < 5 + m < 6$$
$$-6 - 5 < m < 6 - 5$$
$$-11 < m < 1$$
**Final answer:**
The line $y=mx - 5$ does not intersect the curve $y=x^2 - 5x + 4$ for values of $m$ in the interval $$(-11, 1)$$.