LESSON FOUR (17 JUNE 2020) ALGEBRA
GOOD MORNING GRADE 8's
Today we will work with page 110 of your textbook.
The topic is called SUBSTITUTION. Please do not be detered by this long word, it is actually very easy.
The most important thing to remember is that numbers have signs in front of them.
With substitution, we give you the expression with the variables and then we tell you what number the variable represents. All you have to do is insert the number into the sum and solve.
EXAMPLE 1: 5a + 3, where a = 2
This means that in place of a you will insert 2 therefore the sum will be:
5a + 3
= (5x2) + 3
= 10 + 3
= 13
EXAMPLE 2: 5a - 3, where a = -4
be careful, because now i am telling you that the variable is a NEGATIVE NUMBER.
5a - 3
= 5 x (-4) - 3
= -20 - 3
= -23
WORK TO BE DONE IN EXERCISE BOOKS:
ACTIVITY 8.5 page 110
DUE: REMEMBER ANSWERS DONE IN YOUR EXERCISE BOOKS MUST BE SENT TO YOUR TEACHERS, FROM THERE WE WILL SEND YOU THE MEMO. LESSON FOUR IS DUE NO LATER THAN 19 JUNE 2020 @ 15:00. WHATSAPP MESSAGES ARE TO BE SENT ONLY BETWEEN 08:00 AND 15:00 FROM MONDAY TO SATURDAY PLEASE.
NB: If you have not been issued a textbook, please contact me (Mrs Maharaj) urgently!
Details are below:
Mrs Makwara 071 809 2055 vmakwara@alexhigh.org.za
Mrs Cassim 084 786 2585 scassim@alexhigh.org.za
Miss Thwala 083 787 3976 pthwala@alexhigh.org.za
Mrs Hlatshwayo 074 705 6775 mhlatshwayo@alexhigh.org.za
Mrs Maharaj 073 5581246 hmaharaj@alexhigh.org.za
Mr Cele 079 622 1676 bcele@alexhigh.org.za