Solve the System by the Addition Method $$\left\{ \begin{array} { l } 7 x - 2 y = 6 \\- 21 x + 6 y = - 24\end{array} \right.$$

question 19

Multiple Choice

Solve the system by the addition method. If there is no solution or an infinite number of solutions, so state. Use set
notation to express the solution set.
- $$\left\{ \begin{array} { l } 7 x - 2 y = 6 \\- 21 x + 6 y = - 24\end{array} \right.$$

• A) \(\{ ( 7,6 ) \}\)
• B) \(\{ ( 3,4 ) \}\)
• C) no solution; \(\varnothing\)
• D) \(\left\{ \left( \frac { 7 } { 9 } , - \frac { 2 } { 9 } \right) \right\}\)

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Definitions:

Short Tandem Repeat

DNA sequences consisting of a few nucleotides repeated multiple times in a row, used in genetic mapping and fingerprinting.

Polymerase Chain Reaction

A laboratory technique used to amplify segments of DNA for various genetic analyses and applications.

DNA Fingerprinting

A technique used to identify individuals by examining their DNA characteristics, often used in forensic science.

Recombinant DNA

DNA molecules formed by laboratory methods of genetic recombination to bring together genetic material from multiple sources, creating sequences that would not otherwise be found in biological organisms.