1. **State the problem:** Solve the quadratic equation $$7r^2 - 14r = -7$$.
2. **Rewrite the equation:** Move all terms to one side to set the equation to zero:
$$7r^2 - 14r + 7 = 0$$
3. **Simplify the equation:** Divide every term by 7 to simplify:
$$\cancel{7}r^2 - \cancel{7}2r + \cancel{7} = 0 \implies r^2 - 2r + 1 = 0$$
4. **Recognize the quadratic form:** The equation is now:
$$r^2 - 2r + 1 = 0$$
This is a perfect square trinomial.
5. **Factor the quadratic:**
$$r^2 - 2r + 1 = (r - 1)^2 = 0$$
6. **Solve for r:** Set the factor equal to zero:
$$(r - 1)^2 = 0 \implies r - 1 = 0 \implies r = 1$$
**Final answer:**
$$r = 1$$
Quadratic Equation 98523B
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