Solve each system of equations by using elimination.

[tex]\[
\begin{array}{l}
8p + 8q = 19 \\
5p - 5q = 20
\end{array}
\][/tex]

a. [tex]\((3.19, 0)\)[/tex]
b. [tex]\((3.19, -0.81)\)[/tex]
c. [tex]\((1.57, -0.81)\)[/tex]
d. [tex]\((1.38, 3.19)\)[/tex]



Answer :

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

[tex]\[ \begin{array}{l} 8p + 8q = 19 \quad \text{(1)} \\ 5p - 5q = 20 \quad \text{(2)} \end{array} \][/tex]

### Step 1: Align the Coefficients for Elimination

Here, we aim to eliminate one of the variables by aligning coefficients. Let's eliminate [tex]\( q \)[/tex].

### Step 2: Equalize the Coefficients of [tex]\( q \)[/tex]

In order to eliminate [tex]\( q \)[/tex], we need to make the coefficients of [tex]\( q \)[/tex] in both equations opposites. For this, we can multiply equation (1) by 5 and equation (2) by 8:

Multiply equation (1) by 5:
[tex]\[ 5(8p + 8q) = 5 \cdot 19 \\ 40p + 40q = 95 \quad \text{(3)} \][/tex]

Multiply equation (2) by 8:
[tex]\[ 8(5p - 5q) = 8 \cdot 20 \\ 40p - 40q = 160 \quad \text{(4)} \][/tex]

### Step 3: Add or Subtract the Equations to Eliminate [tex]\( q \)[/tex]

Now, add equations (3) and (4) together to eliminate [tex]\( q \)[/tex]:

[tex]\[ (40p + 40q) + (40p - 40q) = 95 + 160 \\ 40p + 40p = 255 \\ 80p = 255 \][/tex]

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

[tex]\[ p = \frac{255}{80} \\ p = 3.1875 \approx 3.19 \][/tex]

### Step 5: Substitute [tex]\( p \)[/tex] Back into One of the Original Equations to Solve for [tex]\( q \)[/tex]

Substitute [tex]\( p = 3.19 \)[/tex] into equation (1):
[tex]\[ 8(3.19) + 8q = 19 \\ 25.52 + 8q = 19 \\ 8q = 19 - 25.52 \\ 8q = -6.52 \\ q = \frac{-6.52}{8} \\ q = -0.815 \approx -0.81 \][/tex]

### Conclusion

After solving, we find the solution to be:

[tex]\[ (p, q) = (3.19, -0.81) \][/tex]

None of the options exactly match our found solution of [tex]\((3.19, -0.81)\)[/tex]. This means the system intersects at [tex]\(\boxed{\text{None of the provided options exactly match the intersection point}}.\)[/tex]