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The Cardinals, Blue Jays, and Hawks participate in a tournament with other teams. Points are awards for wins, draws, and losses.The Cardinals win 6 matches, have 3 draws, and one loss for a total of 40 points.The Blue Jays have 7 wins, 2 draws, and 1 loss for a total of 44 points.The Hawks have 4 wins, 4 draws, and 2 losses for a total of 28 points.How many points were awarded for a win?Select one:a.2b.7c.6d.5

User Alexnnd
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1 Answer

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Let x be the amount of points awarded for a win, y the amount of points awarded for a draw and z the amount of points awarded for a loss.

If a teams wins 6 matches, then the number of points awarded for 6 win games would be


6x

so, we will write an equation for each of the teams.

For the cardinals, they won 6 matches, 3 draws and 1 loss for a total of 40 points. So the equation would be


6x+3y+1z=40

For the blue jays: They won 7 matches, 2 draws and 1 loss for a total of 44 points. So the equation would be


7x+2y+1z=44

Finally, for the hawks, they had 4 wins, 4 draws and 2 losses for a total of 28 points. So we have the equation


4x+4y+2z=28

we want to solve this equations to find the value of x.

We will start by taking the first equation


6x+3y+1z=40

we will take this equation and subtract it from the second one. So we get


\begin{gathered} 7x+2y+1z\text{ - \lparen6x+3y+1z\rparen=44-40} \\ =\text{ 7x -6x +2y-3y+1z-1z=4} \\ =x\text{ -y=4} \end{gathered}

that means, we have the new equation


x\text{ -y=4}

Now. We will take the first equation, multiply it by 2 and subtract it from the third equation. That is


\begin{gathered} 4x+4y+2z\text{ - 2\lparen6x+3y+1z\rparen=28 -2}\cdot40 \\ =4x\text{ - 12x + 4y - 6y +2z - 2z =}28\text{ - 80 } \\ =\text{ -8x-2y= -52} \end{gathered}

if we divide both sides by -2 we get the equation


4x+y=26

Now, let us add this two new equations that we got. That would be


\begin{gathered} x\text{ -y + 4x+y =}4+26 \\ =\text{ x+4x +y -y=30} \\ =\text{ 5x=30} \end{gathered}

then, if divide both sides by 5, we get


\begin{gathered} 5x=30 \\ x=(30)/(5)=6 \end{gathered}

so the number of points awarded for a win is 6

User Danger
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