You can use the method of substitution to solve the given linear system of equations.
The solution of the equation is given by (x,y) = (-3, 6.8)
The value of x is given by option:
Option A: -3
We can use elimination in which we eliminate one variable to get the value of other variable and then use that value to find the first variable's value.
The system of equation given to us is
[tex]4.2x + 8y = 41.8\\-4.2x +y = 19.4\\[/tex]
Since we see that in the both equation have equal and opposite signed coefficient of the variable x, thus we can add both the equations to eliminate x.
Adding both the equations, we get:
[tex](4.2 - 4.2)x + 8y + y = 41.8 + 19.4\\0x + 9y = 61.2\\9y = 61.2\\\\y = \dfrac{61.2}{9} = 6.8[/tex]
Putting this value of y in the first equation, we get:
[tex]4.2x + 8y = 41.8\\4.2x + 8 \times 6.8 = 41.8\\4.2x = -12.6\\\\x = -\dfrac{12.6}{4.2} = -3[/tex]
Thus,
The solution of the equation is given by (x,y) = (-3, 6.8)
The value of x is given by option:
Option A: -3
Learn more about system of linear equations here:
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