1. Solve for $x$: $$2x + 5 = 15$$. 2. Factorize the quadratic expression: $$x^2 - 5x + 6$$. 3. Find the value of $y$ when $$y = 3x^2 - 2x + 1$$ and $x = 4$. 4. Simplify the algebraic expression: $$\frac{2x^2 - 8}{4x}$$. 5. Solve the system of equations: $$\begin{cases} 2x + y = 10 \\ x - y = 2 \end{cases}$$. 6. Expand and simplify: $$(x + 3)^2$$. 7. Determine the slope and intercept of the line represented by the equation $$3x - 4y = 12$$. 8. Calculate the length of the hypotenuse in a right triangle with legs 6 cm and 8 cm using Pythagoras theorem. 9. Find the roots of the quadratic equation $$x^2 + 4x + 3 = 0$$ by completing the square. 10. If the area of a rectangle is 48 square units and its length is 8 units, find the width.