**Multiplying Binomials by Monomials**

Today, we started out with an equation to solve.

- ( x + 7 )

How to solve:

**= -1 ( x + 7 )**

**= -1x + (-1)(7)**

**= -x -7**

**Next equation:**

2(3x + 4)

**Solve:**

= 2(3x)+2(4)

**or**3x+4+3x+4= 6x + 8

**This is called distributive property.**

The trick to answering an equation is to look at the signs very carefully.

**Signs**

**will always confuse you.**

(-)(-) Two negatives makes a

**positive.**(-)(+) One negative makes a

**negative.**(+)(+) Positives makes a

**positive.**

**Example:**

**-2 ( 3x - 4 )**

= -2(3x) + -2(4)

= -6x - 8

**2x ( 3x + 4 )**

= 2x(3x) + 2x(4)

= 6x ² + 8x

**Another way to write this is:**

(2)(3)(x)(x) + (2)(4)(x)

Which equals the same thing.

Now a model can be shown:

**Another equation is:**

**-4x (2x - 3y +5)**

= -4x(2x) + (-4x)(-3y) + (-4x)(5)

= (-4)(2)(x)(x) + (-4)(-3)(x)(y) + (-4)(5)(x)

= -8x ²+ 12xy -20x

Now one more step is missing; which is the equation has to be in alphabetical order for final answer.

**= -8x**²

**- 20x + 20xy**

Homework:

Read pages 264-268

CYU 2 & 3

Practice Odd or Even

2 Apply

Extend - 19 & 20 or 20 & 21

Homework Book 7.2

Extra Practice 7.2

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