Factorise: 3x^2 + 18x + 65
Answers
Answer:
2.1 Factoring 3x2+18x+65
The first term is, 3x2 its coefficient is 3 .
The middle term is, +18x its coefficient is 18 .
The last term, "the constant", is +65
Step-1 : Multiply the coefficient of the first term by the constant 3 • 65 = 195
Step-2 : Find two factors of 195 whose sum equals the coefficient of the middle term, which is 18 .
-195 + -1 = -196
-65 + -3 = -68
-39 + -5 = -44
-15 + -13 = -28
-13 + -15 = -28
-5 + -39 = -44
-3 + -65 = -68
-1 + -195 = -196
1 + 195 = 196
3 + 65 = 68
5 + 39 = 44
13 + 15 = 28
15 + 13 = 28
39 + 5 = 44
65 + 3 = 68
195 + 1 = 196
Answer:
6+18x+65 = 71+18x =
18× = -71.
x = -71-18= -89