Question

ANSWER ASAP PLZ!!

Solve the system by elimination. State whether the system has one solution, infinite solutions, or no solution
0.2-0.3y=4
2.3x- Y=1.2
(x,y)=( answer )

Answer 1

`\text{If is}\\\\\left\{\begin{array}{ccc}0.2-0.3y=4\\2.3x-y=1.2\end{array}`

Answer:

`\large\boxed{\left(-(344)/(69),\ -(38)/(3)\right)}`

Explanation:

`\left\{\begin{array}{ccc}0.2-0.3y=4\\2.3x-y=1.2&\text{multiply both sides by (-0.3)}\end{array}\right\\\\\underline{+\left\{\begin{array}{ccc}0.2-0.3y=4\\-0.69x+0.3y=-0.36\end{array}\right}\qquad\text{add both sides of the equations}\\.\qquad-0.69x+0.2=3.64\qquad\text{subtract 0.2 from both sides}\\.\qquad-0.69x=3.44\qquad\text{divide both sides by (-0.69)}\\.\qquad x=-(3.44\cdot100)/(0.69\cdot100)\\.\qquad \boxed{x=-(344)/(69)}\\\\\text{Calculate the value of y from first equation:}`

`0.2-0.3y=4\qquad\text{subtract 0.2 from both sides}\\-0.3y=3.8\qquad\text{divide both sides by (-0.3)}\\y=-(3.8\cdot10)/(0.3\cdot10)\\\boxed{y=-(38)/(3)}`

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`\text{If is}\\\\\left\{\begin{array}{ccc}0,2x-0,3y=4\\2.3x-y=1.2\end{array}\right`

Answer:

`\large\boxed{\left(-(52)/(7),\ -(128)/(7)\right)}`

Explanation:

`\left\{\begin{array}{ccc}0.2x-0.3y=4&\text{multiply both sides by 10}\\2.3x-y=1.2&\text{multiply both sides by 10}\end{array}\right\\\\\left\{\begin{array}{ccc}2x-3y=40&\text{multiply both sides by (-10)}\\23x-10y=12&\text{multiply both sides by 3}\end{array}\right\\\\\underline{+\left\{\begin{array}{ccc}-20x+30y=-400\\69x-30y=36\end{array}\right}\qquad\text{add both sides of the equations}\\.\qquad49x=-364\qquad\text{divide both sides by 49}\\x=-(364:7)/(49:7)\\.\qquad\boxed{x=-(52)/(7)}`

`2\left(-(52)/(7)\right)-3y=40\\-(104)/(7)-3y=40\qquad\text{multiply both sides by 7}\\-104-21y=280\qquad\text{add 104 to both sides}\\-21y=384\qquad\text{divide both sides by (-21)}\\y=-(384:3)/(21:3)\\\boxed{y=-(128)/(7)}`