Question 16402
5b+15
______

7b+21

Start with the numerator;
5b+15;
to factorout the 5,
5(b+3)
Now the denominator;
7b+21
facot out the 7;
7(b+3)
now you have;
{{{5(b+3)/7(b+3)}}}
Now you can cancel out the (b+3); and your answer would be;
{{{5/7}}}
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