Question

What are the x-coordinates of the solutions to this system of equations?

x2 + y2 = 36
y = x - 6

A. 2 and 0

B. 6 and 2

C. 6 and -2

D. 6 and 0

Answer 1

@YanaSidlinskiy

Answer 2

Is this what the eqautions are?
\[x^2+y^2 = 36\] and
\[y=x-6\]

Answer 3

yes

Answer 4

the second equation, pick a number for x and the results will be for why, and from their. Keep doing that until u have like 3 ordered pairs and draw a line for it .
y = x - 6 and then for the second one, all you have to do is, change the equation and solve for y.
x2 + y2 = 36 change it to y^2 =36 + x^2

Answer 5

Go it? I have to go now.

Answer 6

substitute the second equation into the first and solve for x. There should be 2 values of x. Then substitute the 2 values of x in turn into the second equation to get the 2 corresponding values of y.

Answer 7

You ok with it?

Answer 8

how would i substitute the second equation into the first

Answer 9

x^2 + y^2 = 36
square everything
x + y = 6
x + y = 6
y = x - 6

x+ (x-6) = 6
2x - 6 = 6
2x = 12
x = 6
substitute that into y = x- 6
to get the value for y :)

Answer 10

sorry only asking for the x co-ordinate so no need to substitute back into the second

Answer 11

may I continue @bribri50?

Answer 12

you may

Answer 13

thanks

Answer 14

so the answer is either b, c, or d

Answer 15

\[x^2+y^2=36\]\[y=x-6\]\[x^2+(x-6)^2=36\]

Answer 16

\[x^2+x^2-12x+36=36\]\[2x^2-12x=0\]

Answer 17

Oh, shhoot. Sorry for the incorrections. I have an explanation..

First note that we take y = x - 6 and substiutute that into y in the first equation,
So the FIRST equation becomes x^2 + (x-6)^2 = 36
Simplify the above, you get x^2 + x^2 - 12x + 36 = 36
2x^2 - 12 x = 0
2x(x - 6) = 0
x = 0 or x = 6
If x = 0, y = -6; if x = 6, y = 0
Final solutions: x = 0 and y = -6 AND x = 6 and y= 0

Answer 18

thank you guys

Answer 19

\[x^2-6x=0\]\[x(x-6)=0\] \[x=0 or x=6\]

Answer 20

@YanaSidlinskiy got it before me.

Answer 21

Thanx for noticing my mistake. Hahahaha:D I gave you a medal though:D