First, to calculate the addition of the 2 ratios from the
first equation, we'll calculate the LCD.
LCD = 5*2 =
10
2*(x - 2)/5 +5y/2 =
6*10
We'll re-write the first
equation:
2(x-2) + 5y =
60
We'll remove the
brackets:
2x - 4 + 5y =
60
We'll add 4 both sides:
2x
+ 5y = 60 + 4
2x + 5y = 64
(3)
Now, we'll expande the squares from the second equation
of the system:
(x - 1)^2 -(y - 2)^2 = (x - y)(x + y) -
59
x^2 - 2x + 1 - y^2 + 2y - 1 = (x - y)(x + y) -
59
We'll remove the brackets from the right
side:
(x - y)(x + y) - 59 = x^2 + xy - xy - y^2 -
59
x^2 - 2x + 1 - y^2 + 2y - 1 = x^2 + xy - xy - y^2 -
59
We'll eliminate like
terms:
- 2x + 2y = - 59
(4)
We'll add (3) to (4) and we'll
get:
2x + 5y - 2x + 2y = 64 -
59
We'll eliminate like
terms:
7y = 5
We'll divide by
7:
y =
5/7
We'll substitute y in
(3):
2x + 5*5/7 = 64
2x + 25/7
= 64
7*2x + 25 = 7*64
14x + 25
= 448
We'll subtract 25 both
sides:
14x = 448-25
14x =
423
x =
423/14
The solution of the
system is: {423/14 ; 5/7}.
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