At IDNLearn.com, find answers to your most pressing questions from experts and enthusiasts alike. Ask any question and receive timely, accurate responses from our dedicated community of experts.

55. If the sum of two numbers is 20 and their difference is 4, find the numbers.

A. 12 and 8
B. 14 and 6
C. 15 and 5
D. 13 and 7


Sagot :

Certainly! Let's solve the problem step-by-step.

We are given two key pieces of information about two numbers:
1. Their sum is 20.
2. Their difference is 4.

Let's denote these two numbers as [tex]\( x \)[/tex] and [tex]\( y \)[/tex].

From the given information, we can set up the following system of equations:
1. [tex]\( x + y = 20 \)[/tex]
2. [tex]\( x - y = 4 \)[/tex]

To find the values of [tex]\( x \)[/tex] and [tex]\( y \)[/tex], we can solve these equations simultaneously.

Step 1: Add the two equations

[tex]\[ (x + y) + (x - y) = 20 + 4 \][/tex]

This simplifies to:

[tex]\[ x + y + x - y = 24 \][/tex]

[tex]\[ 2x = 24 \][/tex]

Step 2: Solve for [tex]\( x \)[/tex]

[tex]\[ x = \frac{24}{2} \][/tex]

[tex]\[ x = 12 \][/tex]

Step 3: Substitute the value of [tex]\( x \)[/tex] back into the first equation

[tex]\[ 12 + y = 20 \][/tex]

Step 4: Solve for [tex]\( y \)[/tex]

[tex]\[ y = 20 - 12 \][/tex]

[tex]\[ y = 8 \][/tex]

So, the two numbers are [tex]\( x = 12 \)[/tex] and [tex]\( y = 8 \)[/tex].

Therefore, the correct answer is:

(a) 12 and 8