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26 votes
26 votes
5. The sum of two numbers is 24. The second number is 4 less than the first. Write a system of equations andsolve it to find the numbers.A. (16,8)B. (14, 10)C (18, 14)D (6,4)

User MooingRawr
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1 Answer

10 votes
10 votes

Take x and y as the two numbers, the sum of these is 24:


x+y=24

It is also stated that the second number, y, is 4 less than the first, x, it means:


y=x-4

The system of equations is:


\begin{gathered} x+y=24 \\ y=x-4 \end{gathered}

Use the second equation, which is solved for y and replace this expression for y in the first equation, then solve for x:


\begin{gathered} x+y=24 \\ x+(x-4)=24 \\ x+x-4=24 \\ 2x=24+4 \\ 2x=28 \\ x=(28)/(2) \\ x=14 \end{gathered}

x has a value of 14. Use this value and the second equation to find the value of y:


\begin{gathered} y=x-4 \\ y=14-4 \\ y=10 \end{gathered}

The solution for the system is (14,10). The correct answer is B.

User Angshuman
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