Answer:
m² + 8m + 7 = (m + 1) (m + 7)
m² – 6m + 8 = (m – 2) (m – 4)
Explanation:
If a trinomial ax² + bx + c is "factorable", you can use the AC method.
1. Multiply a and c.
2. Find factors of ac that add up to b.
3. Divide the factors by a and reduce.
4. The numerators are the constants, the denominators are the coefficients.
For example:
m² + 8m + 7
a = 1, b = 8, c = 7
1. ac = 1×7 = 7
2. Factors of 7 that add up to 8 are 1 and 7.
3. Divide by 1: 1/1 and 7/1
4. The factors are (m + 1) and (m + 7).
Therefore, m² + 8m + 7 = (m + 1) (m + 7).
Let's try one with a negative coefficient:
m² – 6m + 8
a = 1, b = -6, c = 8
1. ac = 1×8 = 8
2. Factors of 8 that add up to -6 are -2 and -4.
3. Divide by 1: -2/1 and -4/1
4. The factors are (m – 2) and (m – 4)
Therefore, m² – 6m + 8 = (m – 2) (m – 4).
You can check your answers by distributing.