Hard
Find the roots of the quadratic equation x² + (-7)x + (10) = 0.
Explanation
Explanation
We need two numbers whose sum is 7 and product is 10 (since for x² + bx + c, sum of roots = -b, product = c). Those numbers are 5 and 2, so the equation factors as (x - (5))(x - (2)) = 0, giving x = 5 or x = 2.
PRO TIP
Re-check your working by substituting the answer back into the original question.