To solve the quadratic equation \( x^2 - 13x + 42 = 0 \) by grouping, we need to split the middle term \(-13x\) into two terms such that their sum equals \(-13x\) and their product equals the constant term, \(42\).
We are looking for two numbers that multiply to \(42\) and add up to \(-13\).
We can find these two numbers by considering the factors of \(42\):
- \(1\) and \(42\) (sum: \(43\))
- \(2\) and \(21\) (sum: \(23\))
- \(3\) and \(14\) (sum: \(17\))
- \(6\) and \(7\) (sum: \(13\))
To get \(-13\), we need to take negative values:
- \(-1\) and \(-42\) (sum: \(-43\))
- \(-2\) and \(-21\) (sum: \(-23\))
- \(-3\) and \(-14\) (sum: \(-17\))
- \(-6\) and \(-7\) (sum: \(-13\))
The numbers we need are \(-6\) and \(-7\), since:
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They multiply to \(42\): \[ -6 \times -7 = 42 \]
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They add up to \(-13\): \[ -6 + -7 = -13 \]
Thus, the two numbers needed to split the middle term are \(-7\) and \(-6\).
Given that we enter the lesser value first, the answer is:
\(-7, -6\)