How do you subtract this
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To subtract fractions, you need to obtain a common denominator. We can achieve this, in this case, by multiplying:
[tex](\frac{4}{4} * \frac{22}{13}) - (\frac{13}{13}*\frac{21}{4})[/tex]
Simplify this:
[tex]\frac{88}{52} - \frac{286}{52}[/tex]
Now we have common denominators, so we can easily just subtract the numerators, and we have the answer:
[tex]-\frac{198}{52}[/tex]
Notice that this is divisible by 2:
[tex]-\frac{99}{26}[/tex]
That's your answer!