1. Solving Algebraic Equations
Anne Gilleran
This Photo by Unknown Author is licensed under CC BY-NC-SA
This Photo by Unknown Author is licensed under CC BY-SA

2. Add Subtract Multiply Divide
When we are trying to solve an equation, we are trying to get the Letter on its own on the Left
To get a letter on its own, use the opposite operation (inverse) to undo what is happening!!
What is the inverse operation to:
Add
Subtract
Multiply
Divide

3. 7x = 28
This Photo by Unknown Author is licensed under CC BY-SA

4. 7x = 28 ÷7 ÷7

5. x = 4

6. LO: To solve algebraic equations
The balancing method. =
a + 2 8

7. LO: To solve algebraic equations
The balancing method. =
a + 2 8 -2 -2

8. = a 6

9. Examples:
x + 5 = 13
x – 4 = 8
6c = 18
y/3 = 21

10. 5 6 2 -8 -3 4 3 -1 1 Now you try! a a + 3 = 8 b 6 – a = 2 c 5a = 10
Odd one out! Find the number which is not equal to one of the unknowns!!
a a + 3 = 8
b 6 – a = 2
c 5a = 10
d a + 6 = 3
e -3a = 3
f a/2 = -4
g – a = 6
h /a = 30 5 6 2 -8 -3 4 3 -1 1

11. Two operations! =
2x + 3 13

12. =
2x + 3 13 -3 -3

13. = 2x 10

14. = 2x 10 ÷2 ÷2

15. = 5 x

16. Examples:
4x + 1 = 13
7x – 5 = 44

17. Two operations! Solve the following:
LO: To solve algebraic equations
Two operations! Solve the following:
2a + 5 = (b) 3b – 4 = 17
(c) 2c + 6 = (d) 5d – 2 = 8
(e) 3r + 7 = (f) 8p + 1 = 25
(g) 10n – 7 = (h) 3n – 5 = 19
(i) 3y – 4 = (j) 5z + 13 = 18
(k) e = (L) 1 – 2f = 9
(m) 13 = 3g (n) 5 = 1 + 8h (p) 3 + k = (q) 13 = 12 + m
(r) a – 3 = (s) 10 = 2 - b
a = 4
b = 7
c = 5
d = 2
r = 8
p = 3
n = 4
n = 8
y = 5
z = 1
e = -1
f = -4
g = 6
h = 0.5
m = 3
k = 8
a = 20
b = -24

18. Now you try! LO: To solve algebraic equations
Coach the person next to you to get as far as possible!

19. Make up your own algebraic equation for your partner to solve!!