Consider the following system of equations.

-x+y=5
y=(x-3)^2+2
is (1,6 a solution to the system equation? explain
1) Graph the system of equations
2)using the graph state the solution to the system of equations. (give the smaller point first)
3) could a system of two equations that include a linear equation and a quadratic equation ever have an infinite solutions? if so how could you tell from the graph? if not explain why

1 answer

To assess whether the point (1, 6) is a solution to the system of equations, we'll start by substituting \( x = 1 \) and \( y = 6 \) into both equations.

  1. The first equation is: \[ -x + y = 5 \] Substituting \( x = 1 \) and \( y = 6 \): \[ -1 + 6 = 5 \quad \Rightarrow \quad 5 = 5 \quad \text{(True)} \]

  2. The second equation is: \[ y = (x - 3)^2 + 2 \] Again substituting \( x = 1 \) and \( y = 6 \): \[ 6 = (1 - 3)^2 + 2 \] \[ 6 = (-2)^2 + 2 = 4 + 2 = 6 \quad \Rightarrow \quad 6 = 6 \quad \text{(True)} \]

Since both equations are satisfied by the point (1, 6), it is indeed a solution to the system of equations.

1) Graph the System of Equations

To graph the equations:

  • For the first equation \( -x + y = 5 \) (or \( y = x + 5 \)):

    • The y-intercept is \( 5 \), so one point is (0, 5).
    • The slope is \( 1 \), giving another point at (1, 6).
  • For the second equation \( y = (x - 3)^2 + 2\):

    • This is a parabola that opens upwards, with its vertex at (3, 2).
    • When \( x = 1 \), \( y = (1 - 3)^2 + 2 = 4 + 2 = 6\).
    • When \( x = 5 \), \( y = (5 - 3)^2 + 2 = 4 + 2 = 6\).

You can plot these points and curves on a graph. The linear equation will be a straight line, and the quadratic equation will be a parabola.

2) State the Solution to the System of Equations

From our verification, we found that the point (1, 6) satisfies both equations.

To state the solution using the graph:

  • The two points of intersection are the solutions to the system. Here, we already confirmed (1, 6) is one solution. Depending on the graph, if the parabola intersects the line elsewhere, that would be the second solution.

Assuming no other intersections are evident:

  • Smaller point first: (1, 6)

3) Could a System of Two Equations that Include a Linear Equation and a Quadratic Equation Ever Have Infinite Solutions?

A system of a linear equation and a quadratic equation typically does not have infinite solutions. However, certain conditions allow for infinite solutions:

  1. Same Line and Parabola: If a linear equation coincides with the vertex of a parabola and lies entirely within the parabolic opening (like if the line is a tangent to the parabola at its vertex), infinite solutions can occur where the line touches the parabola at the vertex and continues through.

  2. Graphical Interpretation:

    • If the graph shows that the line is entirely within the curve of the parabola without intersecting it more than once or if they perfectly overlap (i.e., the line is a tangent), then there could be infinite points along the line that satisfy the equations.

In general, for two shapes of different types (like a line and a parabola) to give infinite solutions, they must be perfectly aligned along an entire segment, which is a very specific and rare case. Otherwise, the typical cases of intersection yield either no points, a single point, or two points.