How do I do this??
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Question

How do I do this??
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larseighner · Answer

$$\Large {a \over b} \pm {c \over d} = {{ad \pm bc} \over bd}$$

anonymous · Answer

Can you show me how to do the first one?

larseighner · Answer

$$\Large {a \over b} \pm {c \over d} = {{ad \pm bc} \over bd}$$

$$\Large {6 \over x} + {6 \over 3x} = {{6\cdot 3x + 6\cdot x} \over x\cdot 3x}={24x \over 3x^2} = {8 \over x}$$

anonymous · Answer

So I just multiply by 3 then add then divide?

larseighner · Answer

You have to express both numbers in the numerator with a common denominator. Then add them, then divide.

anonymous · Answer

oh okay. I think I got it. If I need help I'm going to message you okay?

larseighner · Answer

k

anonymous · Answer

Wait. So is the answer supposed to be 8/x?

larseighner · Answer

That is the answer to the fist part.  Part b says x = 24 mph.

anonymous · Answer

oh okay.

anonymous · Answer

okay I just need help on the second one now. It looks different than the first one.

anonymous · Answer

@LarsEighner

larseighner · Answer

$$\Large {a \over b} \pm {c \over d} = {{ad \pm bc} \over bd} $$

In the above, what should you replace a with?

anonymous · Answer

I just dont know what to do with the x+15 part

larseighner · Answer

That is just d. Follow the rule above.  What is ad and bd?

anonymous · Answer

a=325 right??

anonymous · Answer

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