### Home > A2C > Chapter 4 > Lesson 4.2.4 > Problem4-123

4-123.

Consider the system of equations at right: $\left. \begin{array} { l } { 3 y - 4 x = - 1 } \\ { 9 y + 2 x = 4 } \end{array} \right.$

1. What is the parent of each equation?

Both equations are equations of lines.

2. Solve this system algebraically.

Multiply the first equation by $−3$, then use elimination.
Now substitute the value found for $x$ into the equation $3y−4x=−1$ and solve for $y$.

3. Find where the two graphs intersect.

The graphs intersect at the solution to both equations.

4. Explain the relationship between parts (b) and (c) above.

See part (c).