Given the equations:
x^2 +
y^2 = 29..............(1)
x+ y =
7.......................(2)
We have a system of two
equations and two variables. Then, we can use the substitution or the elimination method
to solve.
Let us use the substitution method to
solve.
We will re-write equation
(2).
x+ y = 7
==> y = 7
- x
Now we will substitute in
(1).
x^2 + y^2 = 29
==>
x^2 + ( 7-x)^2 = 29
==> x^2 + 49 - 14x + x^2 =
29
==> 2x^2 - 14x + 49 - 29 =
0
==> 2x^2 - 14x + 20 =
0
Now we will divide by
2:
==> x^2 - 7x + 10 =
0
==> ( x - 2) ( x- 5) =
0
==> x1 = 2 ==> y1= 7-2 =
5
==> x2= 5 ==> y2= 7-5 =
2
Then the answer is the
pairs:
( 2, 5) OR ( 5, 2)
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