Newbie Needs Help Solving Equations

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    Solving equations
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To solve the equations y = -x + 5 and y = x² - 16x + 59, one effective method is to set them equal to each other, resulting in the equation x² - 15x + 54 = 0. This can be solved for x, and the corresponding y values can be found by substituting x back into either original equation. Graphing the equations can also help visualize the number of solutions by identifying intersection points. While some participants express a dislike for sketching graphs, it remains a useful approach for understanding the solutions. The discussion highlights various strategies for tackling such equations, emphasizing the importance of isolating variables or using graphical methods.
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hi everyone! I am new to this site and hope you can help me out a little :)

This is a homework question but am unsure how to do these types of equations

y = - x + 5
y = x² - 16 x + 59

x= and y= or x= and y=

could someone tell me how you go about doing these equations?

Thanks
 
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The general method for this type of problem is to isolate one variable, then use the resulting equation in the second equation to solve for the single remaining variable.

Give it a try and show us what you are doing.
 
another approach, given "easy" equations is to draw the equations on X,Y plane and see how many intersections you get. the number of intersection is the number of (x,y) answers you'll get.
i.e. if you're drawing shows no intersections this means you got no answer...
 
greytomato said:
another approach, given "easy" equations is to draw the equations on X,Y plane and see how many intersections you get. the number of intersection is the number of (x,y) answers you'll get.
i.e. if you're drawing shows no intersections this means you got no answer...

Yeah a rough sketch will show how many solutions you will have. As for solving equations graphically, that's something I hate . As intergral said, you would usually isolate one variable, then solve for that variable. Start by trying to make one equation from the two you are given.
 
bambino9 said:
hi everyone! I am new to this site and hope you can help me out a little :)

This is a homework question but am unsure how to do these types of equations

y = - x + 5
y = x² - 16 x + 59

x= and y= or x= and y=

could someone tell me how you go about doing these equations?

Thanks

Since y= both -x+ 5 and x2- 16x+ 59, them must be equal to each other: x2- 16x+ 59= -x+ 5. Solve that for x, then put those values into y= -x+ 5 to find the corresponding y.
 
there will be equations fom which you cannot isolate X nor Y.
there is where the sketch comes in :)
 
greytomato said:
there will be equations fom which you cannot isolate X nor Y.
there is where the sketch comes in :)

Yeah I know, but I still hate sketching graphs...could be the fact that I can't draw...:rolleyes:
 
Looks like we are talking to ourselfs on this one. The OP has not been back since the origianal posts.

Please refrain from further responses until the OP comes back.
 
Hootenanny said:
Yeah I know, but I still hate sketching graphs...could be the fact that I can't draw...:rolleyes:

A hand drawn plot? I thought everyone just used their calculator these days?
 
  • #10
Integral said:
A hand drawn plot? I thought everyone just used their calculator these days?

I'm still using a bog standard scientific calculator, only one step away from the abacus! If I want anything resembling an accurate plot I usually use autograph.
 
  • #11
Where have you gone, bambino?
 
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