Question

Wayne is solving a system of linear equations.

y = −3/4x + 5
x = −2

To solve this system, he graphed the line y = −3/4x + 5.

When Wayne graphs the line x = −2, at which point will he find the solution of this system of linear equations?

Answer 1

(-2, 6.5)

Explanation:

Wayne can follow the line from (-2, 0) up to where it crosses the graphed line. The crossing point is approximately halfway between 6 and 7 on the graph, so can be considered to be 6.5.

If we put x=-2 into the equation and evaluate, we get ...

... y = (-3/4)(-2) +5 = 6/4 +5 = (1 1/2) +5 = 6 1/2

Thus the solution is (-2, 6 1/2).