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

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

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

7x = 28 ÷7 ÷7

x = 4

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

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

= a 6

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

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 9 – a = 6 h 180/a = 30 5 6 2 -8 -3 4 3 -1 1

Two operations! = 2x + 3 13

= 2x + 3 13 -3 -3

= 2x 10

= 2x 10 ÷2 ÷2

= 5 x

Examples: 4x + 1 = 13 7x – 5 = 44

Two operations! Solve the following: LO: To solve algebraic equations Two operations! Solve the following: 2a + 5 = 13 (b) 3b – 4 = 17 (c) 2c + 6 = 16 (d) 5d – 2 = 8 (e) 3r + 7 = 31 (f) 8p + 1 = 25 (g) 10n – 7 = 33 (h) 3n – 5 = 19 (i) 3y – 4 = 11 (j) 5z + 13 = 18 (k) 11 + 4e = 7 (L) 1 – 2f = 9 (m) 13 = 3g - 5 (n) 5 = 1 + 8h (p) 3 + k = 7 (q) 13 = 12 + m 2 3 (r) a – 3 = 7 (s) 10 = 2 - b 2 3 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

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

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