You can put this solution on YOUR website! find the LCD of:
7/a^2+2a-63 , 8/a+9
Before you can solve this you need to factorise,a^2+2a-63
when you factorise a^2+2a-63, you will get (a - 7)(a + 9)
So therefore taking both denominators thats (a + 9) and a^2+2a-63, the LCM is
(a - 7)(a + 9)
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