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 elimination, we follow these steps:

1. Write down the given system of equations:

[tex]\[
\begin{align*}
(1) & \quad 5a + 5b = 25 \\
(2) & \quad -5a + 5b = 35
\end{align*}
\][/tex]

2. Eliminate one of the variables:

To eliminate [tex]\( a \)[/tex], we can add Equation (1) and Equation (2) together. This method works because the coefficients of [tex]\( a \)[/tex] in the two equations are opposites.

3. Add the equations:

[tex]\[
\begin{align*}
(5a + 5b) + (-5a + 5b) &= 25 + 35 \\
0a + 10b &= 60 \\
10b &= 60
\end{align*}
\][/tex]

We have successfully eliminated the variable [tex]\( a \)[/tex].

4. Identify the resulting equation:

The resulting equation after elimination is [tex]\( 10b = 60 \)[/tex].

Thus, the equation you obtain when using elimination to solve the given system is [tex]\( 10b = 60 \)[/tex].