Mathematics

Fluency · Pack B

Quadratic Equations

Answer each question. Show working where needed.

Bronze
  1. Solve $x^2 = 49$.

  2. Solve $(x - 5)^2 = 0$.

  3. Solve $(x - 3)(x - 7) = 0$.

  4. Factorise $x^2 + 8x + 15$.

  5. Factorise $x^2 - 9x + 20$.

  6. Solve $x^2 + 7x + 10 = 0$.

  7. Factorise $x^2 - 81$.

  8. Solve $x^2 - 36 = 0$.

  9. State the roots of $y = (x - 5)(x + 1)$.

  10. Verify that $x = 2$ is a root of $x^2 - 7x + 10 = 0$.

Silver
  1. Solve $x^2 - 2x - 15 = 0$.

  2. Solve $x^2 = 4x + 12$.

  3. Solve $x^2 = 7x$.

  4. Expand $(x + 7)^2$.

  5. Write $x^2 + 10x$ as $(x + p)^2 - q$.

  6. Write $x^2 + 4x + 9$ in completed-square form $(x + p)^2 + q$.

  7. Use the quadratic formula to solve $x^2 + 7x + 12 = 0$.

  8. Solve $(x + 2)(x - 5) = 8$.

  9. How many real roots does $x^2 - 6x + 9 = 0$ have?

  10. Solve $(x + 2)^2 = 25$.

Gold
  1. Factorise $3x^2 + 10x + 7$.

  2. Use the quadratic formula to solve $3x^2 + 10x + 7 = 0$.

  3. Write $x^2 - 10x + 18$ in completed-square form.

  4. Solve $x^2 + 4x + 1 = 0$ by completing the square (give exact answers).

  5. Solve $x^2 + 4x + 10 = 0$.

  6. Solve $x^2 - 6x - 2 = 0$, giving exact answers.

  7. The roots of $x^2 + 7x + 12 = 0$ are $\alpha$ and $\beta$. State $\alpha + \beta$ and $\alpha \beta$.

  8. If $x = 4$ is a root of $x^2 + bx - 4 = 0$, find $b$.

  9. Find a monic quadratic equation with roots $-1$ and $6$.

  10. Solve $(x - 3)^2 = 11$, giving exact answers.

Platinum
  1. For what values of $k$ does $x^2 + 4x + k = 0$ have two distinct real roots?

  2. A rectangular garden is $x$ m wide and $(x + 4)$ m long. Its area is $60$ m². Find $x$.

  3. Write $2x^2 - 12x + 7$ in the form $a(x + p)^2 + q$.

  4. A ball is thrown upward and its height $h$ (m) after $t$ s is given by $h = 30t - 5t^2$. When does it hit the ground (other than at $t = 0$)?

  5. Solve $2x^2 - 7x - 4 = 0$ exactly.

  6. A right-angled triangle has legs of length $x$ and $(x + 1)$ cm. Its hypotenuse is $5$ cm. Find $x$.

  7. The quadratic $x^2 - 6x + c = 0$ has roots that differ by 2. If one root is $4$, find $c$ and $b$.

  8. Solve $x^2 + 6x + 4 = 0$ exactly, in surd form.

  9. The equation $x^2 + kx + 9 = 0$ has exactly one (repeated) real root. Find $k$.

  10. The product of two consecutive positive integers is $132$. Find the integers.