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Please help! .........

Please help! .........-example-1
User Jim Biard
by
6.5k points

1 Answer

5 votes

Answer:

1) When x is 1, y is 4, and vice versa

2) When x is -6, y is 42, and when x is 7, y is 114

3) When x is -2, y is 2, and when x is 8, y is 42

Explanation:

1)


y=x^2-6x+9


y+x=5 which can be rearranged as
y=5-x.

Substituting this lone y into the first equation, you get:


5-x=x^2-6x+9

Move everything to one side:


x^2-5x+4=0

Factor:


(x-4)(x-1)=0


x=1, 4


y=4, 1

2)


y-30=12x which can be rearranged as
y=12x+30.


y=x^2+11x-12

Let's use elimination this time and subtract the first equation from the second:


0=x^2-x-42

Factor:


(x-7)(x+6)=0


x=-6, 7


y= -42, 114

3)


y=x^2-2x+6


y=4x+10

Let's set the two equations equal to each other through substitution:


x^2-2x-6=4x+10

Move everything to one side:


x^2-6x-16=0

Factor:


(x-8)(x+2)=0


x=-2, 8


y= 2, 42

Hope this helps!

User Mtsr
by
6.6k points
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