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Question from Kimi, a student:

I am stuck on this,can someone please help me????

1/2x+1/3y=11
8x+2/5y=102
Can someone please explain how to solve questions like these??
Or else I will never learn...
Thank you

Hi Kimi,

First you need to take care of the way you type mathematics. When you type 1/2x I don't know if you mean $\frac{1}{2x}$ or $\frac{1}{2} x.$ I expect you mean $\frac{1}{2} x$ so you should type (1/2) x.

The subject line of your email was "Simultaneous equations with fractions" so I expect it is the fractions that are creating your dilemma I would start be eliminating the fractions. For example with your second equation

\[8x + \frac25 y = 102\]

the only denominator is 5 so I would multiply each side by 5 and simplify to get

\[40x + 2y = 510.\]

This equation is equivalent to your second equation but has no fractions.

In your first equation there are two denominators 2 and 3 so you can multiply by 2 and then by 3 to find an equivalent equation with no fractions but you can accomplish this in one step by multiplying both sides by $2 \times 3 = 6.$ Try it.

You should now have two equations with no fractions. Can you solve them?

Write back if you need more assistance,
Penny

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