Solve Quadratic Equation: Finding Study Days When Reading 30+4x Pages Daily

To solve this problem, we'll need to correctly setup and solve an equation that relates all given quantities. Here are the steps:

• Step 1: Setup the equation.
  Since Andrea reads $30 + 4x$ pages per day and studies for $x + 5$ days, the total number of pages she reads is: $(30 + 4x)(x + 5) = 4x^2 + 650$
• Step 2: Expand and simplify the equation.
  Expanding the left-hand side, we have: $(30 + 4x)(x + 5) = 30(x + 5) + 4x(x + 5)$ $= 30x + 150 + 4x^2 + 20x$ Combine like terms: $= 4x^2 + 50x + 150$ Now, equate to the total pages: $4x^2 + 50x + 150 = 4x^2 + 650$
• Step 3: Simplify and solve for $x$.
  Subtract $4x^2$ from both sides: $50x + 150 = 650$ Subtract 150 from both sides: $50x = 500$ Divide by 50: $x = 10$ Since Andrea studies for $x + 5$ days, substitute $x = 10$: $x + 5 = 10 + 5 = 15$

Therefore, Andrea studies for $\mathbf{15}$ days.