Discover the answers to your questions at Westonci.ca, where experts share their knowledge and insights with you. Connect with a community of experts ready to provide precise solutions to your questions quickly and accurately. Connect with a community of professionals ready to provide precise solutions to your questions quickly and accurately.

Solve the system of equations using elimination and identify the solution. List your answers in alphabetical order in the ordered pairs.

[tex]\[ 2a + z = 4 \][/tex]
[tex]\[ 3a - 7z = 6 \][/tex]

A. [tex]\((2,0)\)[/tex]
B. [tex]\(\left(\frac{1}{2}, \frac{1}{2}\right)\)[/tex]
C. [tex]\((0,2)\)[/tex]
D. No Solution
E. Infinitely Many Solutions

Sagot :

We're given the system of equations:

1) [tex]\(2a + z = 4\)[/tex]

2) [tex]\(3a - 7z = 6\)[/tex]

We will solve this system using the method of elimination.

Step 1: Align the equations for elimination
First, we want to eliminate one of the variables. Let's aim to eliminate [tex]\(z\)[/tex]. To do this, we'll make the coefficients of [tex]\(z\)[/tex] in both equations equal (in magnitude) but opposite in sign.

The coefficients of [tex]\(z\)[/tex] in the first and second equations are 1 and -7, respectively. Let's find a common multiple of these coefficients. The least common multiple of 1 and 7 is 7.

Multiply the first equation by 7 to make the coefficient of [tex]\(z\)[/tex] match (but opposite) that of the second equation:

[tex]\[7(2a + z) = 7 \cdot 4\][/tex]

This gives us:

[tex]\[14a + 7z = 28\][/tex]

Step 2: Rewrite the system
Now we have:

1') [tex]\(14a + 7z = 28\)[/tex]

2) [tex]\(3a - 7z = 6\)[/tex]

Step 3: Add the equations
Adding these two equations will eliminate [tex]\(z\)[/tex]:

[tex]\[ (14a + 7z) + (3a - 7z) = 28 + 6 \][/tex]

Simplify:

[tex]\[14a + 3a + 7z - 7z = 28 + 6\][/tex]

This reduces to:

[tex]\[17a = 34\][/tex]

Step 4: Solve for [tex]\(a\)[/tex]
Divide both sides by 17:

[tex]\[a = \frac{34}{17} = 2\][/tex]

Step 5: Use [tex]\(a\)[/tex] to solve for [tex]\(z\)[/tex]
Now substitute [tex]\(a = 2\)[/tex] back into one of the original equations to solve for [tex]\(z\)[/tex]. We'll use the first equation:

[tex]\[2a + z = 4\][/tex]

Substitute [tex]\(a = 2\)[/tex]:

[tex]\[2(2) + z = 4\][/tex]

[tex]\[4 + z = 4\][/tex]

Subtract 4 from both sides:

[tex]\[z = 0\][/tex]

Step 6: Write the solution as an ordered pair
We've found [tex]\(a = 2\)[/tex] and [tex]\(z = 0\)[/tex]. So the solution to the system is:

[tex]\(\boxed{(2, 0)}\)[/tex]

Therefore, the correct answer is [tex]\((2, 0)\)[/tex].