Solving Simultaneous Equations by Elimination

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Solving Simultaneous Equations by Elimination
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Solve the simultaneous equations 4t 3r 28 2t
3r 8
Solve the simultaneous equations 3k p 8 2k
p 17

• 4t 3r 28 (1)
• 2t 3r 8 (2)
• - (2) 2t 20
• t 10
• Substitute into (2)
• 20 3r 8
• 20 8 3r
• 12 3r
• r 4

• 3k p 8 (1)
• 2k p 17 (2)
• (2) 5k 25
• k 5
• Substitute into (2)
• 10 p 17
• p 17 10
• p 7

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Solve the simultaneous equations 2t 5r 24 t
3r 13
Solve the simultaneous equations 3h 4m 13 2h
3m 3

• 3h 4m 13 (1)
• 2h 3m 3 (2)
• x3 9h 12m 39
• x4 8h 12m 12
• (1) (2) 17h 51
• h 3
• Substitute into (2)
• 6 3m 3
• 3m -3
• m -1

• 2t 5r 24 (1)
• t 3r 13 (2)
• x3 6t 15r 72
• x5 5 t 15r 65
• (1) (2) t 7
• Substitute into (2)
• 7 3r 13
• 3r 13 7
• 3r 6
• r 2