Question

@phi Can you please help me with this problem

Answer 1

@phi

Answer 2

try multiplying top and bottom by 12

Answer 3

what do you mean? There is five fractions which is ridiculous!

Answer 4

when you see something complicated, focus on one piece at a time.
even thought it looks complicated, we know we can multiply top and bottom by the same thing and not change the value.

For starters, multiply the bottom by 12.
can you do that ?

Answer 5

\[\frac{ x }{ 36 } + \frac{ y }{ 48 }\]

Answer 6

to multiply the bottom by 12:
first step:
write down the bottom part:
\[ \frac{x}{3}+ \frac{y}{4} \]

2nd step:
multiply it by 12. Be sure to use parens
\[ 12 \cdot \left( \frac{x}{3}+ \frac{y}{4} \right) \]

3rd step:
distribute the 12 (which means multiply each term inside the parens by 12)
can you do step 3?

Answer 7

remember, when you multiply a whole number by a fraction
it is the same as
\[ \frac{12}{1} \cdot \frac{x}{3} \]
multiply top times top and bottom times bottom.
notice you can simplify

Answer 8

\[4x+\frac{ 1 }{ 4 }y\]

Answer 9

the first part is ok. but 12(a+b) is 12a+ 12b
in other words, you should multiply both terms by 12

Answer 10

if you think of the parens as a "package" you have 12 packages, which means you have 12 of everything inside the package.

Answer 11

what do you get for
\[ 12 \cdot \left( \frac{x}{3}+ \frac{y}{4} \right) \]?

Answer 12

4x+3y

Answer 13

yes, that is good.

so far we have
\[ \frac{12 \cdot \left( \frac{x}{4}- \frac{y}{3} \right)}{4x+3y} \]

now simplify the top

Answer 14

3x-4y

Answer 15

So the answer is D
\[\frac{ 3x-4y }{ 4x+3y }\]

Answer 16

notice that multiplying by 12 "clears the denominator" and simplifies both the top and bottom. I picked 12 because both 3 and 4 divide into 12