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Multiplying Binomials Assignment Multiply.
1. (x + 5)² ​

2 Answers

5 votes

Answer:

x² + 10x + 25

Explanation:

Hey!

We're using the FOIL method;

(x + 5)(x + 5) = First: x times x equals x²

Outer: x times 5 equals 5x

Inner: 5 times x equals 5x

Last: 5 times 5 equals 25

(x + 5)² = x² + 10x + 25

Therefore, (x + 5)² equals x² + 10x + 25.

User Matthew Darnell
by
8.7k points
6 votes

Answer:

x² + 10x + 25

Explanation:

Binomial Expansion

To expand the expression (x + 5)², we can use the formula for the square of a binomial, which states:

  • (a + b)² = a² + 2ab + b²

Binomial Expansion - Calculations

In this case, we have a = x and b = 5, so we can substitute these values into the formula to get:

(x + 5)² = x² + 2(x)(5) + 5²

= x² + 10x + 25

FOIL Method

An alternative method to answering this question is using the FOIL method, which uses the following steps:

Multiply the:

1. First Terms

2. Outside Terms

3. Inside Terms

4. Last Terms

Then, add all of the terms together.

FOIL Method - Calculations

Since we are squaring (x + 5), we can multiply the expression by itself:


(x + 5)(x + 5)

Then, we can perform the FOIL method:

First Terms


(\underline{x}+5)(\underline{x}+5)


x* x=x^2

Outside Terms


(\underline{x}+5)(x+\underline{5})


x* 5 = 5x

Inside Terms


(x+\underline{5})(\underline{x}+5)


x* 5 = 5x

Last Terms


(x+\underline{5})(x+\underline{5})


5* 5 = 25

Finally, add the terms together:


x^2+5x+5x+25

Simplify:


\huge\boxed{x^2+10x+25}

Final Answer

Therefore, the expanded form of (x + 5)² is x² + 10x + 25.