Learn how to solve a system of equations by substitution

The video tutorial demonstrates how to solve a system of equations using the substitution method. It begins by explaining the concept of substitution, where a value is substituted for a variable. The tutorial then walks through the process of substituting the expression for one variable into another equation, solving for the variable D, and finally using the value of D to find the value of C. The solution set is determined as D = 2 and C = -6.

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