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One equation from a system of two linear equations is graphed on the coordinate grid. 51 46 5 4 3 2 1 6 x -1 -21 The second equation in the system of linear equations has a slope of 3 and passes through the point (2,-5). What is the solution to the system of equations? th

User Thomas Luechtefeld
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1 Answer

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First, we need to find the equation for the two equations.

The equation graphed has a y-intercept of 3 and a slope of


m=(-6)/(3)=-3

therefore, the equation of the line is


\boxed{y=-(1)/(2)x+3.}

For the second equation, we know what it has a slope of 3; therefore it can be written as


y=3x+b

Now, we also know that this equation passes through the point y = -5, x = 2; therefore,


-5=3(2)+b

which gives


-5=6+b
b=-11

Hence, the equation of the line is


\boxed{y=3x-11}

Now we have the equations


\begin{gathered} y=-(1)/(2)x+3 \\ y=3x-11 \end{gathered}

equating them gives


-(1)/(2)x+3=3x-11

adding 11 to both sides gives


-(1)/(2)x+14=3x

adding 1/2 x to both sides gives


14=(7)/(2)x

Finally, dividing both sides by 7/2 gives


\boxed{x=4\text{.}}

The corresponding value of y is found by substituting the above value into one of the equations


y=-(1)/(2)(4)+3
y=1

Hence, the solution to the system is


(4,1)_{}

User Slajma
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