Help needed, i'm stuck. What is the simplified form of the quantity x squared minus 5x plus 6 over 15 x y squared all over the quantity 2x squared minus 7x plus 3 over 5 x squared y?
Sounds like you're dealing with this? \[\Large \frac{x^2-5x+6}{15xy}\div\frac{2x^2-7x+3}{5x^2y}\] Anyways, I'll let @Lord_Box answer this one
\[\frac{ x^2-5x+6 }{ 15xy^2} \div \frac{ 2x^2-7x+3 }{ 5x^2y }\] Just with a square on the first y.
Alright when dividing a fraction by another fraction, how is this accomplished?
Cross multiplication?
Yes, multiplying the top of one by the bottom of the other, and vice versa. Can you show me what that would look like?
Cross multiplication only happens if you set two fractions equal to each other
6x2-5x+y+6?
Alright, I'll clear it up. When you divide one fraction by another, you "flip the second fraction and multiply.\[\frac{ x^2-5x+6 }{ 15xy^2 } \times \frac{ 5x^2y }{ 2x^2-7x+3 }\]
okay
hint: try to factor `x^2-5x+6` and `2x^2-7x+3`
the first one is (x-2)(x-3) I couldn't figure out the second
You can factor the second one by grouping. First, multiply the coefficients of the first and last terms, 2 * 3 = 6. What two numbers multiply to 6 but add to - 7?
-6 and -1
Right, so you can rewrite this as 2x^2 - 6x - x +3. Think of these as two parts, 2x^2 - 6x, then -x + 3, can you identify the common factor that goes into both of these?
I'll help you out, -x + 3 fits into both of these. Once you find this greatest common factor, you need to take it out of both:\[2x^2-6x-x+3 = 2x(x-3) -1(x-3) = (2x-1)(x-3)\]
the beginning should read x-3 instead of -x+3, sorry
okay
so right now we have \[\frac{ (x-2)(x-3) }{ 15xy^2 } \times \frac{ 5x^2y }{ (2x-1)(x-3) }\] What all could you cancel out?
(x-3)
see the attached text document to see another way to factor `2x^2-7x+3`
\[\frac{ (x-2) }{ 15xy^2 } \times \frac{ 5x^2y }{ (2x-1) }\] Good, you cancelled the (x-3), but there's still more that can be simplified. HINT: top right, bottom left
Thank you @jim_thompson5910 Oh, okay XD
one is 5x^2y and the other is 5xy^2
Hint: \[\Large \frac{5x^2y}{15xy^2}=\frac{5*x*x*y}{3*5*x*y*y}\] \[\Large \frac{5x^2y}{15xy^2}=\frac{{\color{red}{5}}*{\color{blue}{x}}*x*{\color{purple}{y}}}{3*{\color{red}{5}}*{\color{blue}{x}}*{\color{purple}{y}}*y}\]
oh
That's a detailed way to show that the '5's will pair up and cancel out, a pair of 'x's will cancel out. So will a pair of 'y's. What is left over when all that canceling is done?
5x and 3y
the '5's will cancel
oh
\[\Large \frac{5x^2y}{15xy^2}=\frac{5*x*x*y}{3*5*x*y*y}\] \[\Large \frac{5x^2y}{15xy^2}=\frac{{\color{red}{5}}*{\color{blue}{x}}*x*{\color{purple}{y}}}{3*{\color{red}{5}}*{\color{blue}{x}}*{\color{purple}{y}}*y}\] \[\Large \frac{5x^2y}{15xy^2}=\frac{{\color{red}{\cancel{5}}}*{\color{blue}{x}}*x*{\color{purple}{y}}}{3*{\color{red}{\cancel{5}}}*{\color{blue}{x}}*{\color{purple}{y}}*y}\]
yeah, i got confused XD
I now have x and 3y
Yes, so \[\Large \frac{5x^2y}{15xy^2} = \frac{x}{3y}\] which means \[\Large \frac{ (x-2) }{ 15xy^2 } \times \frac{ 5x^2y }{ (2x-1) }\] turns into \[\Large \frac{ (x-2) }{ 3y } \times \frac{ x }{ (2x-1) }\]
Good stuff. Let's recap: \[\frac{ (x-2) }{ 3y } \times \frac{ x }{ (2x-1) }\]
\[\frac{ x(x-2) }{ 3y(2x-1)}\]
okay, thank you for the help!
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