Solve the System of Equations by Graphing $\left\{ \begin{array} { l } x + y = 1 \\x - y = - 3\end{array} \right.$

question 12

Multiple Choice

Solve the system of equations by graphing.
- $\left\{ \begin{array} { l } x + y = 1 \\x - y = - 3\end{array} \right.$

• A) (2, -1)
• B) no solution
• C) (-1, 2)
• D) (-1, -2)

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Definitions:

IgD

An antibody class (immunoglobulin D) involved in the immune system’s response to antigens, present in small amounts in the body's fluids and tissues.

IgE

Immunoglobulin E, a class of antibodies produced by the immune system that plays a key role in allergic reactions.

Allergic Responses

Immune system reactions to a substance that most people tolerate well, characterized by symptoms such as itching, swelling, and difficulty breathing.

Interleukin

A substance that is a messenger between leukocytes.