 LESSON
Algebra
an hour ago by
16 slides

# Algebra

by AuMihi Tapara # ​Learning Intentions:

​We are learning to:

• ​solve algebra equations by finding the value of a letter

• ​combine like terms using algebra equations

​Success Criteria:

• ​name the value of a letter to make our algebra equation correct

• ​combine all like terms using algebra equations

Q.

What is the value of a?

a + 5 = 12

12 - a = 5

​a + 5 = 12

​12 - a = 5

We need to find which number we would use instead of a to make this equation correct.

5

6

7

8

# ​What is the value of a?

​a + 5 = 12

​12 - a = 5

We need to find which number we would use instead of a to make this equation correct.

​If a = 7 then:

​7 + 5 = 12

​12 - 7 = 5

Q.

What is the value of a?

a x 5 = 25

25 ÷ 5 = a

We need to find which number we would use instead of a to make this equation correct.

5

10

15

20

# ​What is the value of a?

​a x 5 = 25

​25 ÷ 5 = a

​We need to find which number we would use instead of a to make this equation correct.

​If a = 5 then:

​5 x 5 = 25

​25 ÷ 5 = 5

# ​Multiplying in algebra

​You may also see terms like this in algebra: 2a or 7a

​When there is no equation symbol between the number and letter, you need to multiply.

​2a = 10 or 2 x a = 10

​Therefore a = 5

​7a = 14 or 7 x a = 14

​a = 2

Q.

What is the value of a?

8a = 32

2

4

6

8

Q.

What is the value of a?

12a = 36

2

3

4

5

# ​What if the letter changes?

​It doesn't matter which letter is shown in an algebraic equation when you are finding the value.

​If 2a = 10 then a = 5

​If 2b = 10 then b = 5

​If 2c = 10 then c = 5

​If 2z = 10 then z = 5

​The letters are there to represent an unknown number.

# What is a like term in algebra?

​A like term in algebra is a value that is the same.

​a is the same as a

​b is the same as b

​If I have 2a + 3a this means that I have 2 of the letter a plus 3 of the letter a. These are like terms as the letter is the same. Therefore I would have 5a in total.

​If I have 2a + 3b, this would mean that I have 2 of the letter a and 3 of the letter b. These are different letters so I would not add them together.

# ​Combining like terms

​Watch the following video:

​https://youtu.be/CLWpkv6ccpA

Q.

6a + 3a =

6 + 3 + a

9a

a + a

a + a + a + a + a + a + a + a + a

Q.

2a + 6a + 5a =

8a

11a

13a

15a

Q.

2a + 3b + 5a =

7a + 3b

2a + 8b

10a

2a + 3b

Q.

6b + 3c + 2b + 5c + 4d 