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pokemon23
 3 years ago
If y = 5x + 2, then find the value of
10xy + 4y in terms of y.
pokemon23
 3 years ago
If y = 5x + 2, then find the value of 10xy + 4y in terms of y.

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bahrom7893
 3 years ago
Best ResponseYou've already chosen the best response.1wow u didn't type @bah here...

bahrom7893
 3 years ago
Best ResponseYou've already chosen the best response.1I'm not smart enough????

bahrom7893
 3 years ago
Best ResponseYou've already chosen the best response.1y=5x+2 y2 = 5x x = (1/5)(y2)

bahrom7893
 3 years ago
Best ResponseYou've already chosen the best response.110xy + 4y = 10 (1/5)(y2) y + 4y = 2(y  2)y + 4y = 2y^2  4y + 4y = 2y^2 <Final answer

pokemon23
 3 years ago
Best ResponseYou've already chosen the best response.0o_o I'm taking the PSAT... I don't know how to do these types of questions......

Calcmathlete
 3 years ago
Best ResponseYou've already chosen the best response.3To clarify on what @bahrom7893 said, I would've done something a bit simpler? \[\implies10xy + 4y~~~~~~~~~~Original~Expression\]\[\implies 2y(5x + 2)~~~~~~~~~Factor~out~the~GCF\]\[\implies 2y(y) ~~~~~~~~~~~~~~~~~~Substitute\]\[\implies 2y^2~~~~~~~~~~~~~~~~~~~~~Multiplication~of~variables\]

pokemon23
 3 years ago
Best ResponseYou've already chosen the best response.0ok let's do another problem I need to get better.

Calcmathlete
 3 years ago
Best ResponseYou've already chosen the best response.3Uh ok then... \[y = (3x + 2)^3\]\[\text{Simplify in terms of y: } (9x + 6)^3\]

Calcmathlete
 3 years ago
Best ResponseYou've already chosen the best response.3Very similar to the one you were doing on that PSAT question.

pokemon23
 3 years ago
Best ResponseYou've already chosen the best response.0so do I multiply to the 3rd power?

Calcmathlete
 3 years ago
Best ResponseYou've already chosen the best response.3Yes, the \(^{'3'}\) implies cubing it or multiplying by itself 3 times.

Calcmathlete
 3 years ago
Best ResponseYou've already chosen the best response.3Not quite...could you show me what you did?

pokemon23
 3 years ago
Best ResponseYou've already chosen the best response.0well you its dw:1349998059319:dw so i multiply the exponent to the 3rd?

Calcmathlete
 3 years ago
Best ResponseYou've already chosen the best response.3If you were to actually multiply it out, it would be like doing this: \[(9x + 6)^3 \implies (9x + 6)(9x + 6)(9x + 6)\]which is unnecessary here. Again, like previous times, do you see anything that you can factor out?

pokemon23
 3 years ago
Best ResponseYou've already chosen the best response.0i keep forgetting to factor.....

pokemon23
 3 years ago
Best ResponseYou've already chosen the best response.0my spectacles are deceiving me

pokemon23
 3 years ago
Best ResponseYou've already chosen the best response.0ok if we can (9x+6) (9x+6) (9x+6)

Calcmathlete
 3 years ago
Best ResponseYou've already chosen the best response.3THat is not a step that we even need to take, but we can solve it using that. It would be a slightly longer process though. Let's work WITHIN the parentheses first. Don't do anything ith the \(^3\) for now.

pokemon23
 3 years ago
Best ResponseYou've already chosen the best response.0ok will keep it (9x+6)^3

Calcmathlete
 3 years ago
Best ResponseYou've already chosen the best response.3Now factor what's within the parentheses...

Calcmathlete
 3 years ago
Best ResponseYou've already chosen the best response.3The 3 wouldn't go outside of the parentheses because it's still under the \(^3\), so it would become \((3(3x + 2))^3\) Do you see why that is?

pokemon23
 3 years ago
Best ResponseYou've already chosen the best response.0explain those parentheses

Calcmathlete
 3 years ago
Best ResponseYou've already chosen the best response.3Well, let's take the approach that you had before. \[(9x + 6)^3 \implies (9x + 6)(9x + 6)(9x + 6) \implies 3(3x + 2)3(3x + 2)3(3x + 2)\]\[3 \times 3 \times 3(3x + 2)(3x + 2)(3x + 2) \implies 3^3(3x + 2)^3~~~OR~~~27(3x + 2)^3\]See what I did? You can't take the 3 \(\LARGE{ENTIRELY}\) out of the parentheses unless you take the \(^3\) with it.

Calcmathlete
 3 years ago
Best ResponseYou've already chosen the best response.3\[\LARGE{¿Entiendes?}\]

Calcmathlete
 3 years ago
Best ResponseYou've already chosen the best response.3Can you predict what to do next?

Calcmathlete
 3 years ago
Best ResponseYou've already chosen the best response.3What? Keep in mind the original question and what y is equal to...

pokemon23
 3 years ago
Best ResponseYou've already chosen the best response.0then we should substitute

Calcmathlete
 3 years ago
Best ResponseYou've already chosen the best response.3\[\huge\color{red}{Y}\color{blue}{E}\color{salmon}{S}\color{green}{!}\]

pokemon23
 3 years ago
Best ResponseYou've already chosen the best response.0instead of the x make it a y?

Calcmathlete
 3 years ago
Best ResponseYou've already chosen the best response.3Uh...remember that \(y = (3x + 2)^3...\) You can substitute y in for that value now. Tell me what your final answer would be now.

Calcmathlete
 3 years ago
Best ResponseYou've already chosen the best response.3Umm...no... \[(9x + 6)^3 \implies (3(3x + 2))^3 \implies 3^3(3x + 2)^3 \implies 27(3x + 2)^3 \implies 27y\]

Calcmathlete
 3 years ago
Best ResponseYou've already chosen the best response.3Do you see why? Do you understand what it means when it says "in terms of y"? Do you see that we're replacing ALL OF \((3x + 2)^3\) with y? That way nothing in that is cubed anymore?

pokemon23
 3 years ago
Best ResponseYou've already chosen the best response.0I still don't get how divided 27(3x+2)^3 to get 27y

Calcmathlete
 3 years ago
Best ResponseYou've already chosen the best response.3Where do you see a division symbol? There is no division invloved in this except the beginning factoring portion. \[\large{\text{We just clarified that y}}~\LARGE\text{=}~\large{(3x + 2)^3}\]Just replace \((3x + 2)^3\) with y and that's all that happened.

pokemon23
 3 years ago
Best ResponseYou've already chosen the best response.0where does (3x+2)^3? disappear?

pokemon23
 3 years ago
Best ResponseYou've already chosen the best response.0I don't understand the y part...

Calcmathlete
 3 years ago
Best ResponseYou've already chosen the best response.3fdiofvejbvnweokgnweoifnerwo That is what we're substituting with y! Remember when we said y = 2 and we plugged it in? Well we could say that 2 = y and we plug y in for the 2. SAME THING HERE. y = (3x + 2)^3 (3x + 2)^3 = y Now you just plug in why for the (3x + 2)^3
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