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Solve the simultaneous equations

2x + 4y = 1
3x - 5y = 7
y=1.5 x=
What does x equal

User Liu Tao
by
3.6k points

1 Answer

4 votes

Answer:

The solution to the system of equations be:

x = 0.5, y = -0.5

Explanation:

Given the system of equations


\begin{bmatrix}2x+4y=1\\ 3x-5y=7\end{bmatrix}

Multiply 2x+4y=1 by 3: 6x+12y=3

Multiply 3x-5y=7 by 2: 6x-10y=14


\begin{bmatrix}6x+12y=3\\ 6x-10y=14\end{bmatrix}

subtracting the equations


6x-10y=14


-


\underline{6x+12y=3}


-22y=11

solve -22y for y


-22y=11

Divide both sides by -22


(-22y)/(-22)=(11)/(-22)

Simplify


y=-(1)/(2)


y = -0.5

For 6x+12y=3 plug in y = -1/2


6x+12\left(-(1)/(2)\right)=3


6x-12\cdot (1)/(2)=3


6x-6=3

Add 6 to both sides


6x-6+6=3+6


(6x)/(6)=(9)/(6)

Simplification


x=(3)/(2)


x = 1.5

Therefore, the solution to the system of equations be:

x = 0.5, y = -0.5

User Sethu
by
3.5k points