Question

How do you graph the system of equations `21x + 7y = 42` and `- 5x + 5y = 10`?

Answer 1

Plot each equation on the same graph using arbitrary solutions (at least 2 points) for each equation.

Explanation:

For the equation: `color(red)(21x+7y=42)`
two possible solutions are:
#color(white)("XXX"){: (color(red)underline(x),color(white)("XX"),color(red)underline(y)), (color(red)0,,color(red)6), (color(red)2,,color(red)(0)) :}#

For the equation: `color(green)(-5x+5y=10)`
two possible solutions are:
#color(white)("XXX"){: (color(green)0,color(white)("XX"),color(green)2), (color(green)(-2),,color(green)0) :}#

Plotting these points (and drawing a line through each equations pair of points):