AI Math Solver
Resources
Questions
Pricing
Login
Register
Home
>
Questions
>
Solve System of Inequalities \( y \leq (x + 1)^2 - 4 \) and \( y > 2x + 1 \) (Algebra 2)
Mathematics (Algebra 2)
Grade 10 (High School)
Question Content
Sketch the solution to the system of inequalities \( y \leq (x + 1)^2 - 4 \) and \( y > 2x + 1 \), then identify one solution to the system.
Correct Answer
One solution is \((-3, -2)\) (other valid points exist).
Detailed Solution Steps
1
1. Analyze \( y \leq (x + 1)^2 - 4 \): The quadratic \( (x + 1)^2 - 4 \) is a parabola opening upward with vertex at \((-1, -4)\). The inequality \( \leq \) means the parabola is solid, and we shade below it.
2
2. Analyze \( y > 2x + 1 \): This is a linear line with slope \( 2 \) and \( y \)-intercept \( 1 \). The inequality \( > \) means the line is dashed, and we shade above it.
3
3. Identify the overlapping region (solution): Solve \( (x + 1)^2 - 4 = 2x + 1 \) to find intersection points: \( x^2 - 4 = 0 \) → \( x = 2 \) or \( x = -2 \) (points \((2, 5)\) and \((-2, -3)\)). Test the point \((-3, -2)\):
4
- For \( y \leq (-3 + 1)^2 - 4 \): \( -2 \leq 4 - 4 \) → \( -2 \leq 0 \) (true).
5
- For \( y > 2(-3) + 1 \): \( -2 > -6 + 1 \) → \( -2 > -5 \) (true). Thus, \((-3, -2)\) is a solution.
Knowledge Points Involved
1
Intersection of Quadratic and Linear Graphs
To find where a quadratic and linear graph intersect, solve their equations simultaneously (set \( ax^2 + bx + c = mx + b \)) and solve for \( x \), then find \( y \).
2
Solution Region for Mixed Inequalities
The solution to a system with a quadratic (\( \leq \)) and linear (\( > \)) inequality is the overlap of the region below the parabola and above the line, bounded by their intersection points.
3
Testing Points in Bounded Regions
For a bounded solution region (between intersection points), test points within the interval to confirm the overlap; ensure the point satisfies all inequalities.
Loading solution...