Simultaneous Equations substitution

C1: Simultaneous equations KUS objectives BAT solve simultaneous equations by substitution Starter: Solve

and 4y=8x−16 So 𝑥 2 − 8x−16 =9 So x = 1 y = -2 x = 7 y = 10 substitution method WB 6a and 4y=8x−16 So 𝑥 2 − 8x−16 =9 Substitute in So Now we can solve it! x = 1 y = -2 x = 7 y = 10

try this one WB 6b and So Substitute in So Now we can solve it!

Extension: try this evil one WB 7a and  Substitute in Now we can solve it!

Extension: another evil Q WB 7b and So Substitute in Multiply out So Gather together! Simplify!

Practice 2 answers f) a) g) b) h) c) i) d) j) e)

Challenge J 2010 STEP I Question 1

One thing to improve is – KUS objectives BAT solve simultaneous equations by substitution self-assess One thing learned is – One thing to improve is –

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The answers… a) x = 3, y = 1 or x = -7, y = -3 b) x = -4, y = 2 or x = -2, y = 4 c) x = 2, y = 5 or x = 4, y = 7 d) x = -2 , y = 5 one answer only back e) x = 3, y = 1 or x = -1, y = -3 f) x = 1, y = 5 or x = 4, y = 8 g) x = 1, y = 2 or x = 3, y = 0 h) x = -3, y = -11 or x = -7, y = -19 i) x = -3, y = 1 or x = -13/5 , y = 9/5 a) x = 2 , y = 2 or x = -1, y = 16/5