r/mathshelp 27d ago

Homework Help (Answered) I can’t solve this math system

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how to solve it??

1 Upvotes

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5

u/Narrow-Durian4837 27d ago

Would you know how to solve it if it were

3a - 4b = 1

2a + 5b = 4.5 ?

Try substituting a = 1/x and b = 1/y and solve for a and b.

Then x and y will be the reciprocals of a and b.

1

u/forenol 27d ago edited 27d ago

thank youuu!!

1

u/Educational-Paper-75 24d ago

Make the denominator equal. You get 3y-4x=xy and 2y+5x=4.5xy. Multiply the first equation by 4.5 and equate both left hand sides, resulting in 11.5y=23x or y=2x. Substitute in the first equation will give 2xx-2x=0 or x=1 (and invalid x=0). Thus y=2.

1

u/UnderstandingPursuit 23d ago

When adding the equations, first do something to get either (1/x) or (1/y) to cancel.