SOLUTION: If 100-2xy-y^2=x^2, which of the following must be true? a. x-y=10 b. x^2+y^2=100 c. (x+y)(x-y)=100 d. (x+y)^2=100 e. (x-y)^2=100 please explain how to solve this for me, it

Question 393556: If 100-2xy-y^2=x^2, which of the following must be true?
a. x-y=10
b. x^2+y^2=100
c. (x+y)(x-y)=100
d. (x+y)^2=100
e. (x-y)^2=100
please explain how to solve this for me, its been awhile.
Found 2 solutions by richard1234, mananth:
Answer by richard1234(7193) (Show Source): You can put this solution on YOUR website!
The equation is equivalent to

Since factors to we have

, so choice D is correct.
Answer by mananth(16946) (Show Source): You can put this solution on YOUR website!
If 100-2xy-y^2=x^2, which of the following must be true?
a. x-y=10
b. x^2+y^2=100
c. (x+y)(x-y)=100
d. (x+y)^2=100
e. (x-y)^2=100
please explain how to solve this for me, its been awhile.
...
100-2xy-y^2=x^2
bring all the variables to the right side of the equation
100 = x^2+2xy+y^2
...
use the formula

a=x,b=y
100=(x+y)^2
OPTION D
...
m.ananth@hotmail.ca
RELATED QUESTIONS
For which of the following equations is y a function of x? Explain how you know. a. 𝑥 (answered by ikleyn)
If x^2 + y^2 = 2xy, then x must equal ? A) �1 B) 0 C) 1 D) �y E)... (answered by palanisamy,Alan3354)
0 < x < 10, and x ≠ 1.Which of the following must be true? A) x^2 > x B) x^2 >... (answered by susanaramya)
solve the system x^2+y^2=100 y=x^2-3x-10... (answered by ankor@dixie-net.com,greenestamps)
solve algebraically x^2+y^2=100 x+y=2 (answered by Alan3354)
If x and y are negative integers, which of the following expressions must be negative ? (answered by palanisamy)
please help me if any one can............... (if 10^x/10^y=100,then x.......options are (answered by ewatrrr)
Solve the following system of equations algebraically: x^2+y^2=100... (answered by ankor@dixie-net.com)
Which equation does not represent a line of symmetry for the circle with equation... (answered by ikleyn)