What’s my number? (making algebraic equations) 1.Think of a number 2.Make an equation that includes your number 3.Replace your number with an x 4.Pass your equation to your partner & get them to work out what you number is. e.g. (15x3)+7 = 52 3x + 7 = 52
If each sheep is 0.5m long, how long is a cow? 5c = 3c c – 3c = 3.5 2c = 3.5 2c = 3.5 – 0.5 2c = 3 c = 1.5 Each cow is 1.5 metres
If each sheep is 0.5m long, how long is a cow? 4c = 2c + 3 4c – 2c = 3 2c = 3 – 0.5 2c = 2.5 c = 1.25 Each cow is 1.25 metres
33 metres 19 metres Solving simultaneous equations (by elimination)
33 metres 38 metres Find x (the length of a car)length 5x + 4y = 33 3x + 2y = 19 (a) 6x + 4y = 38 (a x2) 5x + 4y = 33 x = 5 Find y (the length of a lorry) (5 x 5) + 4y = y = 33 4y = 33 – 25 4y = 8 y = 2 Solving simultaneous equations (by elimination) 19 metres