Substitute x=7/2 into the first equation.
2 x - 5 y = 2
2(7/2 ) - 5 y = 2
7 - 5y = 2
-7 -7
---------------------
- 5y = -5
-5 -5
y = 1
Check by substituting x = 7/2 and y = 1
into the second equation.
4 x + 5 y = 19
4(7/2) + 5(1) = 19
14 + 5 = 19 Correct!
Solution : x = 7/2 , y = 1
Find values for x and y that solve
both equations simultaneously.
2x - 5y = 2
4x + 5y = 19
We can add the two equations together.
Then -5y and +5y will be eliminated.
2x - 5y = 2
+ 4x + 5y = 19
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2x + 4x - 5y + 5y = 21
6x + 0y = 21
6x = 21
Divide both sides by 6:
6x = 21 -----> x = 7/2
6 6
Simultaneous Equations - Solving without Graphing
