Consider the following system of equations:

-x + y = 5
y = ( x - 3) 2 + 2
Consider the following system of equations:
B. Solve the system of equations using substitution.
c. Graph the system of equations on a piece of graph paper. On the graph, label the
solution(s) to the system of equations.
d. Could a system of two equations that includes a linear equation and a quadratic equation
ever have an infinite number of solutions? If so, how could you tell from the graph? If not,
explain why. in 1 sentence

1 answer

B. Substitute to solve the system of equations.

To solve the system of equations:

  1. From the first equation, solve for \(y\): \[ y = x + 5 \]

  2. Now substitute this expression for \(y\) into the second equation: \[ x + 5 = (x - 3)^2 + 2 \]

  3. Expand the right-hand side: \[ x + 5 = (x^2 - 6x + 9) + 2 \] \[ x + 5 = x^2 - 6x + 11 \]

  4. Rearranging gives: \[ 0 = x^2 - 7x + 6 \]

  5. Factor the quadratic: \[ 0 = (x - 6)(x - 1) \]

  6. Thus, \(x = 6\) or \(x = 1\).

  7. Substitute these values back to find \(y\):

    • For \(x = 6\): \[ y = 6 + 5 = 11 \]
    • For \(x = 1\): \[ y = 1 + 5 = 6 \]

So, the solutions are \((6, 11)\) and \((1, 6)\).

C. Graph the equations.

  1. Graph the linear equation:

    • The line represented by \(-x + y = 5\) can be rewritten as \(y = x + 5\), which has a slope of 1 and a y-intercept at (0, 5).
  2. Graph the quadratic equation:

    • The equation \(y = (x - 3)^2 + 2\) is a parabola that opens upwards, with the vertex at (3, 2).
  3. Label the points of intersection:

    • The points of intersection, which are the solutions, are \((6, 11)\) and \((1, 6)\).

D. Could a system of two equations that includes a linear equation and a quadratic equation ever have an infinite number of solutions?

No, a system of two equations consisting of a linear equation and a quadratic equation cannot have an infinite number of solutions because the linear equation represents a straight line, while the quadratic equation represents a parabola; they can intersect at most twice in the Cartesian plane.