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anonymous
 one year ago
Help Please!!!
Solve the following system of equations and show all work.
y = x2 + 3
y = x + 5
anonymous
 one year ago
Help Please!!! Solve the following system of equations and show all work. y = x2 + 3 y = x + 5

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anonymous
 one year ago
Best ResponseYou've already chosen the best response.0Or anyone that can help me

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0what do you mean by "solve?"

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0I'm not sure thats all they told us.

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0you would write it: x+5=x2+3 and then solve from there. the reason that is corrret is because youre just repacing y with what y is equal to y

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0do the substitution method where you multiple one of the equations by 1

NotTim
 one year ago
Best ResponseYou've already chosen the best response.0Do not do what ew.sorry said. it may work, but @arek 's method is much, much safer.

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0Okay I will. For the substitution method do I make y 1? Sorry I'm not that great at math.

whpalmer4
 one year ago
Best ResponseYou've already chosen the best response.1\[y=x^2+3\]\[y=x+5\] Those are two equations to solve. A couple of routes you can take: substitution setting the two right hand sides equal to each other substitution means solving one equation for one variable in terms of the other. Then you substitute for that variable in the other equation. In this problem, this would a fine way to go because the first step has already been done for you: you have \(y=x+5\) as one of the equations, and that gives you \(y\) in terms of \(x\). Take the other equation \((y = x^2+3)\) and replace \(y\) with \(x+5\), then solve for the values of \(x\). There will be two solutions thanks to the \(x^2\) term, although in some cases they may turn out to be the same value. another approach (which is really substitution as well) is to notice that we have two equations with the same thing on one side. Here, both equations have \(y\) by itself on one side of the equals sign. We can simply set the other two sides equal to each other, because they are equal to the same thing. After that, you solve just as before. In both approaches, after you find the value(s) of \(x\), you plug them into one of the original equations to find the corresponding values of \(y\).

whpalmer4
 one year ago
Best ResponseYou've already chosen the best response.1Another approach would be to graph the two equations and observe where they intersect. \[y=x^2+3\]is a parabola, and \[y=x+5\]is a line. The line crosses the parabola in two locations, which are the solutions to this system.

whpalmer4
 one year ago
Best ResponseYou've already chosen the best response.1And yet another approach, if you had the luxury of a multiplechoice problem where you could know that the answers are provided and you merely need to identify the correct answers, would be to plug each set of answers into all of the equations and select the answer choice where all of the equations work. Note well that you can have "answers" that work for some equations but all...the technical term for them is "wrong" :)

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0Wow! Thank you so much!

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0dw:1433532657818:dw

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0I'm stuck at this point. Did I do it wrong?

whpalmer4
 one year ago
Best ResponseYou've already chosen the best response.1\[x^2+3=x+5\] collect everything on one side, what do you get?

whpalmer4
 one year ago
Best ResponseYou've already chosen the best response.1Yes, or \[x^2x2 = 0 \] Do you know how to factor that equation, or solve it with the quadratic formula, or complete the square?

whpalmer4
 one year ago
Best ResponseYou've already chosen the best response.1@torvia you still here?

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0Yes sorry my dad had to use the computer

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0I know how to solve using quadratic formula

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0dw:1433535440928:dw

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0did i do that right?

whpalmer4
 one year ago
Best ResponseYou've already chosen the best response.1close, but not close enough. I'm intrigued by how you went from \[\sqrt{1+8}\] to \[\sqrt{4}\]in particular :)

whpalmer4
 one year ago
Best ResponseYou've already chosen the best response.1I think you probably just didn't read your handwriting...

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0Yeah sorry it was really messy.

whpalmer4
 one year ago
Best ResponseYou've already chosen the best response.1correct answer is...

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0My solutions then would be 2 and 2?

whpalmer4
 one year ago
Best ResponseYou've already chosen the best response.1let's try them out! \[x^2x2=0\]\[(2)^2(2)2=0\]\[422=0\checkmark\] you do the other one (x=2)

whpalmer4
 one year ago
Best ResponseYou've already chosen the best response.1we are just verifying that we solved for \(x\) correctly here...

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0\[x^2x2 = 0\] \[2^2(2)2 =0\] 4+22 = 0 4 = 0

whpalmer4
 one year ago
Best ResponseYou've already chosen the best response.1Hmm. maybe one of those solutions is incorrect :)

anonymous
 one year ago
Best ResponseYou've already chosen the best response.02 won't be a solution

whpalmer4
 one year ago
Best ResponseYou've already chosen the best response.1by the way, you really need to write \[(2)^2\]instead of \[2^2\] The first one is \((2)*(2) = 4\) and the second one is \((2)(2) = 4\)

whpalmer4
 one year ago
Best ResponseYou've already chosen the best response.1I'll speed things along a little bit: \[\frac{1\pm\sqrt{9}}{2} = \frac{1+3}{2},\frac{13}{2} = \frac{4}{2},\frac{2}{2} = 2,1\]

whpalmer4
 one year ago
Best ResponseYou've already chosen the best response.1and if we try \(1\) in the equation: \[(1)^2 (1)2=0\]\[1+12=0\checkmark\] Now, you can plug those two values of \(x\) into one of the equations and find the corresponding values of \(y\).

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0okay so then y will equal 7 and 4

whpalmer4
 one year ago
Best ResponseYou've already chosen the best response.1Yep! And if you plug them all in to all the equations, they should all work.
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