Week 5 blog post

On this chapter, we learned Factoring Polynomial Expressions.

We learned important five words.

Common 15x+5xy -> 5x(5+y)

Difference of squares $x^2$ – 81 -> (x+9)(x-9)

Pattern $x^2$ +x+# $x^2$ +8x+12

product(12) sum(8)

1* 12 2*6
2* 6
3* 4

Easy $1x^2$

$x^2$ +17x+72 product(72) : 1*72, 2*36, 3*24, 4*18, 6*12, 8*9 sum(17) : 8*9 (x+8)(x+9)

Ugly $ax^2$

$5x^2$ -7x+2 product(10) : 1*10, 2*5 sum(-7) : 2*5 (5x-2)(x-1)

In Factoring Polynomial Expressions, there are some difficult case.

ex) $x^2$ +1.5x+0.5 -> $x^2$ + $\frac{15x}{10}$ + $\frac{5}{10}$

-> $\frac{10x^2}{10}$ + $\frac{15x}{10}$ + $\frac{5}{10}$

-> Find Common Factor $\frac{1}{2}$ ( $2x^2$ +3x+1) product(2) : 1*2 sum(3) : 1*2

-> $\frac{1}{2}$ (2x+1)(x+1)

In this case, we have to solve it this way. In this chapter, to find common factor is very important.

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