Simulataneous equation with surds

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Im trying a question from one of my textbooks which asks me to solve simultaneously:

5x-3y = 41 and (7√2)x + (4√2)y = 82

Ive tried elimination and substitute methods but the surds confuse me so i would appreciate it if anyone can come up with some guidelines of how i should approach this question.

thanks
 
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There is nothing special about the surds. Two suggestions if they confuse you:
  • Replace the coefficients 7\surd2 and 4\surd2 with named parameters such as a and b. Solve and then replace a and b with the known values.
  • Multiply both sides of the second equation by \surd2.
 
david18 said:
Im trying a question from one of my textbooks which asks me to solve simultaneously:

5x-3y = 41 and (7√2)x + (4√2)y = 82

Ive tried elimination and substitute methods but the surds confuse me so i would appreciate it if anyone can come up with some guidelines of how i should approach this question.

thanks
Numbers are numbers! Just go ahead and solve the equations the way you would if there were no "surds". For example, you could multiply the second equation by 3 and multiply the first equation by 4\sqrt{2}, then add the equations to eliminate y.
 
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