SOLUTION: This problem is not from a textbook. Solve the system. X2+y2=145 X+y=17 The answer choices are (9,8) (8,9) (-9,-8) (-8,-9) (-9,8) (-8,9) (9,-8) (8,-9)

Algebra ->  Rational-functions -> SOLUTION: This problem is not from a textbook. Solve the system. X2+y2=145 X+y=17 The answer choices are (9,8) (8,9) (-9,-8) (-8,-9) (-9,8) (-8,9) (9,-8) (8,-9)       Log On


   

Question 134398: This problem is not from a textbook. Solve the system.
X2+y2=145
X+y=17
The answer choices are
(9,8) (8,9)
(-9,-8) (-8,-9)
(-9,8) (-8,9)
(9,-8) (8,-9)
Answer by jim_thompson5910(35256) About Me  (Show Source):
You can put this solution on YOUR website!
x%2By=17 Start with the second equation


y=17-x Subtract x from both sides


x%5E2%2By%5E2=145 Now move onto the second equation


x%5E2%2B%2817-x%29%5E2=145 Plug in y=17-x


x%5E2%2B289-34x%2Bx%5E2=145 Foil


x%5E2%2B289-34x%2Bx%5E2-145=0 Subtract 145 from both sides


2x%5E2-34x%2B144=0 Combine like terms


2%28x-9%29%28x-8%29=0 Factor the left side



Now set each factor equal to zero:
x-9=0 or x-8=0

x=9 or x=8 Now solve for x in each case


So our x values are

x=9 or x=8



y=17-9 Now plug in x=9 into y=17-x

y=8

So the first ordered pair is (9,8)

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y=17-8 Now plug in x=8 into y=17-x

y=9

So the second ordered pair is (8,9)



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Answer:


So the ordered pairs are
(9,8) and (8,9)


which means that the answer is A