I'd appreciate some help!! I need this done ASAP!

Question in first comment

Question

I'd appreciate some help!! I need this done ASAP!

Question in first comment

anonymous · Answer

attachment

anonymous · Answer

@DAVPAS1 Do you mind trying to help me on this one? If not it's fine :) Thx

hartnn · Answer

we need to isolate x.

4/5 is "multiplied" with x.

what is the operation inverse of multiplication?

anonymous · Answer

@hartnn Division

hartnn · Answer

right

so divide 4/5 on both sides,

which is equivalent to multiplying 5/4 on both sides

hartnn · Answer

any doubts?

anonymous · Answer

Multiply by 5/4 because multiplying by the reciprocal always simplifies to 1, which is what you want the coefficient of x to be.

anonymous · Answer

@hartnn Yeah...

hartnn · Answer

what did you not get?

anonymous · Answer

I divided 4/5 on both sides I got 1 and 1/10... Those aren't any of the answer choices :/

hartnn · Answer

in general, dividing by a/b is equivalent to multiplying by b/a 

$\dfrac{Y}{\dfrac{a}{b}} = Y \times \dfrac{b}{a}$

$X = \dfrac{8}{\dfrac{4}{5}} = 8 \times \dfrac{5}{4}$

hartnn · Answer

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