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36 votes
36 votes
Find the value of two numbers if their sum is 751 and their difference is 255

User David Liu
by
2.6k points

2 Answers

15 votes
15 votes

Answer:

y=248

x=503

Explanation:

I will solve this like using a system of linear equations.

Lets set up the equations using your given information.

1) x+y=751

2) x-y=255

We can use one equation to substitute for a variable in another. However, first, we need to manipulate the equation. I will use the second equation to substitute into the first.

x=y+255

Substitute into the first equation.

y+255+y=751

2y+255=751

2y=751-255

2y=496

y=248

Now we can use our known y value to find the x value.

248+x=751

x=503

User Mseery
by
2.6k points
30 votes
30 votes

we can write the sum of two numbers like this:


x+y

and their difference like this:


x-y

then,in this case, we have the following system of equations:


\begin{gathered} x+y=751 \\ x-y=255 \end{gathered}

If we add both of them together we get the following:


\begin{gathered} x+y=751 \\ x-y=255 \\ -------- \\ 2x=1006 \\ \Rightarrow x=(1006)/(2)=503 \\ x=503 \end{gathered}

now that we have the value of x, we can use it on any equation to find the value of y:


\begin{gathered} 503+y=751 \\ \Rightarrow y=751-503=248 \\ y=248 \end{gathered}

therefore, x = 503 and y = 248

User Lafferc
by
2.8k points