Question

The system of equations may be solved by hand calculation or by using the crossing-graphs method.Solve the system of equations shown below by hand calculation3x + 2y = 95x - 5y = 15(x,y)= (_____,______)

Answer 1

Given the system of equations;

3x + 2y = 9 ( multiply by 5)

5x - 5y = 15 ( multiply by 2)

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15 x + 10 y = 45

10 x - 10 y = 30

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25x = 75

Divide both sides by 25

x = 75/25 = 3

Substitute with x at the first equation:

3 * 3 + 2 y = 9

9 + 2y = 9

2y = 9 - 9

2y = 0

y = 0

so, the solution is x = 3 and y = 0

So, ( x , y ) = ( 3 , 0 )