Answer:
1/63
Step-by-step explanation:
There are a couple of ways to do this.
<h3>1) </h3>
Look for the GCF of the numerators when a common denominator is used.
GCF(3/7, 4/9) = GCF(27/63, 28/63) = (1/63)·GCF(27, 28)
GCF(3/7, 4/9) = 1/63
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<h3>2) </h3>
Use Euclid's algorithm. If the remainder from division of the larger by the smaller is zero, then the smaller is the GCF; otherwise, the remainder replaces the larger, and the algorithm repeats.
(4/9)/(3/7) = 1 remainder 1/63*
(3/7)/(1/63) = 27 remainder 0
The GCF is 1/63.
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* The quotient is 28/27 = 1 +1/27 = 1 +(1/27)(3/7)/(3/7) = 1 +(1/63)/(3/7) or 1 with a remainder of 1/63.
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<em>Additional comment</em>
3/7 = (1/63) × 27
4/9 = (1/63) × 28
so we plug in the numbers (hypothenuse is always C in the equation) 
now we solve:
Exponents 
Subtract