What does the word Algebra actually mean Algebra

What does the word ‘Algebra’ actually mean? Algebra is when we use a letter to represent ( stand for ) a value or number But why use a letter when we can use a number? Unfortunately, we can’t always put a number or value to an amount so that’s when we use letters or Algebra

12 eggs in this box. . There are ____ We don’t need algebra we can use a number !!

There are ____ smarties We don’t know how much. . We need a letter to hold the number we don’t know!!

• Important Points… Points

Important Points… Points •

Collecting Like Terms KEYWORD : SIMPLIFY = 3 y = 5 b = 3 a + 2 b = 3 g – 5 n = 6 y + 4 t

Example •

• Simplify these expressions = COLLECT LIKE TERMS

LIKE & UNLIKE TERMS • b & b are LIKE terms • a & b are UNLIKE terms • Terms which use different powers are not like terms • z and z 2 are not like terms. They cannot be collected together!

Mini - whiteboards SUBSTITUTION: What is the value of y? y = 3 r - 10 when r = 3 y = 3 c – 5 when c = -1 y = f 2 + 7 when f = 5 y = 7 x when x = 10 y = 12 w + 12 when w = 6 y=a– 4 when a = -2 B –+ 8 b whenb. B==73 yy==13 when y = 8 ty+=11 2 Q – 9 when t=4 Q=8

Algebra: expressions • Writing Expressions • Simplifying expressions by collecting like terms • Substituting numbers instead of letters in expressions