To solve the quadratic equation \( x^2 - 13x + 42 = 0 \) by grouping, you need to split the middle term, which is \(-13x\), into two terms that add up to \(-13\) and multiply to \(42\) (the constant term).
We need to find two numbers that satisfy:
- \( a + b = -13 \)
- \( a \cdot b = 42 \)
To find these numbers, we can list the pairs of factors of \(42\):
- \(1 \times 42\)
- \(2 \times 21\)
- \(3 \times 14\)
- \(6 \times 7\)
Next, we check which pair can be adjusted (as negatives) to sum to \(-13\):
- \(-1\) and \(-42\) ➔ sum is \(-43\)
- \(-2\) and \(-21\) ➔ sum is \(-23\)
- \(-3\) and \(-14\) ➔ sum is \(-17\)
- \(-6\) and \(-7\) ➔ sum is \(-13\)
The correct pair is \(-6\) and \(-7\).
Thus, the two numbers needed to split the middle term are \( -6 \) and \( -7 \) (with the lesser value first).
So, the answer is:
-6, -7