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H.M. Murdock
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I had a hard time completing the square of some problems. This is what I did with them, I would appreciate if someone could show me the mistake that I am doing and the right process in order to solve these problems.
Also, here there is an article about completing the square for anyone that dosent remeber about it.
http://www.uncwil.edu/courses/mat111hb/Izs/asolve/asolve.html#compsqr
First problem
Complete the square on y = 3xsquare - x + 1 to write it in the form y = a (x - h)square +k
y = 3xsquare - x +1
3xsquare/3 and - x/3 =
3 (xsquare - 1/3x) +1
(1/3)square = 1/9
3 (xsquare -1/3x + 1/9) + 1 - 1/3
The answer is y = 3 (x + 1/3) square 2/3
But the answer on my book is y = 3 (x - 1/6) square + 11/12
I d like to know what was wrong there.
Second problem
Complete the square on y = xsquare - 6x + 10 to write it in the form y = a (x -h)square +k
y = xsquare - 6x + 10
(xsquare -6x) + 10
(-6/2)square = 9
(xsquare - 6x + 9) 10 - 9
The answer is (x + 3)square + 1
However on my book the aswer is y = (x - 3)square + 1
I don't really know where did that "-3" came from.
Third problem
-What are the x- and y- intercepts for f(x) = 2xsquare + x - 6 ?
This quadratic funtions is in the form " axsquare + bx + c " so I used the formula " h = -b/2a "
in order to solve it.
a = 2 and b = 1 on the function
so h = -1/2(2) = -1/4
k = 2(-1/4) square + (-1/4) - 6
k = 1/8 - 1/4 - 6
k= 49/8
I would appreciate if anyone is able to tell me how to solve these 3 problems.
Thanks a lot in advance.
Also, here there is an article about completing the square for anyone that dosent remeber about it.
http://www.uncwil.edu/courses/mat111hb/Izs/asolve/asolve.html#compsqr
First problem
Complete the square on y = 3xsquare - x + 1 to write it in the form y = a (x - h)square +k
y = 3xsquare - x +1
3xsquare/3 and - x/3 =
3 (xsquare - 1/3x) +1
(1/3)square = 1/9
3 (xsquare -1/3x + 1/9) + 1 - 1/3
The answer is y = 3 (x + 1/3) square 2/3
But the answer on my book is y = 3 (x - 1/6) square + 11/12
I d like to know what was wrong there.
Second problem
Complete the square on y = xsquare - 6x + 10 to write it in the form y = a (x -h)square +k
y = xsquare - 6x + 10
(xsquare -6x) + 10
(-6/2)square = 9
(xsquare - 6x + 9) 10 - 9
The answer is (x + 3)square + 1
However on my book the aswer is y = (x - 3)square + 1
I don't really know where did that "-3" came from.
Third problem
-What are the x- and y- intercepts for f(x) = 2xsquare + x - 6 ?
This quadratic funtions is in the form " axsquare + bx + c " so I used the formula " h = -b/2a "
in order to solve it.
a = 2 and b = 1 on the function
so h = -1/2(2) = -1/4
k = 2(-1/4) square + (-1/4) - 6
k = 1/8 - 1/4 - 6
k= 49/8
I would appreciate if anyone is able to tell me how to solve these 3 problems.
Thanks a lot in advance.
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