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PLEASE HELP !! 50 POINTS

PLEASE HELP !! 50 POINTS-example-1

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Answer:


\textsf{ 2x + 4y = 6 $\longrightarrow $ Multiply by $\boxed{\; 3}$ on both sides}


\textsf{ 3x + 5y = 7 $\longrightarrow $ Multiply by $\boxed{\; 2}$ on both sides}

Explanation:

To eliminate the x-terms in the system of equations
\sf 2x + 4y = 6 and
\sf 3x + 5y = 7, we can manipulate the equations to make the coefficients of x in both equations the same or multiples of each other.

In this case, we want to eliminate the x-terms by making the coefficients the same.

First, let's find the least common multiple of 2 and 3, which is 6.

Multiply the first equation by 3 and the second equation by 2:


\sf \begin{aligned} 3(2x + 4y) &= 3(6) \\ 2(3x + 5y) &= 2(7) \end{aligned}

This results in the following system of equations:


\sf \begin{aligned} 6x + 12y &= 18 \\ 6x + 10y &= 14 \end{aligned}

Now, the coefficients of x in both equations are the same (6).

We can subtract the second equation from the first to eliminate the x-terms:


\sf \begin{aligned} (6x + 12y) - (6x + 10y) &= 18 - 14 \\ 2y &= 4 \end{aligned}

Now, we can solve for y by dividing both sides by 2:


\sf y = 2

Now that we have the value for y, we can substitute it back into either of the original equations to solve for x. Let's use the first equation:


\sf 2x + 4(2) = 6

Solving for x:


\sf 2x + 8 = 6

Subtracting 8 from both sides:


\sf 2x = -2

Dividing by 2:


\sf x = -1

So, the solution to the system of equations is
\sf x = -1 and
\sf y = 2.

Therefore, the answer is:


\textsf{ 2x + 4y = 6 $\longrightarrow $ Multiply by $\boxed{\; 3}$ on both sides}


\textsf{ 3x + 5y = 7 $\longrightarrow $ Multiply by $\boxed{\; 2}$ on both sides}

User Hikari Iwasaki
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