College

Which could be the resulting equation when elimination is used to solve the given system of equations?

[tex]
\[
\begin{cases}
5a + 5b = 25 \\
-5a + 5b = 35
\end{cases}
\]
[/tex]

A. [tex]10a = 60[/tex]

B. [tex]10b = 60[/tex]

C. [tex]-10a = 60[/tex]

D. [tex]-10b = 60[/tex]

Answer :

To solve the given system of equations using the elimination method, follow these steps:

The system of equations is:
1. [tex]\( 5a + 5b = 25 \)[/tex]
2. [tex]\( -5a + 5b = 35 \)[/tex]

The goal of the elimination method is to add or subtract the equations to eliminate one of the variables. Let's eliminate the variable [tex]\( a \)[/tex].

Step 1: Add the two equations together to eliminate [tex]\( a \)[/tex].

- Equation 1: [tex]\( 5a + 5b = 25 \)[/tex]
- Equation 2: [tex]\( -5a + 5b = 35 \)[/tex]

Add these two equations:
[tex]\[
(5a + 5b) + (-5a + 5b) = 25 + 35
\][/tex]

Step 2: Simplify the resulting equation.

When you add the left-hand sides of the equations, the [tex]\( a \)[/tex] terms ([tex]\( 5a \)[/tex] and [tex]\(-5a\)[/tex]) cancel each other out:
[tex]\[
5a - 5a + 5b + 5b = 10b
\][/tex]

Thus, the resulting equation is:
[tex]\[
10b = 60
\][/tex]

Therefore, using the elimination method, the resulting equation after eliminating [tex]\( a \)[/tex] is [tex]\( 10b = 60 \)[/tex].