Which is the best approximate solution of the system of equations? (Use the graphing calculator tool to graph the system. Round to the nearest tenth.)
–2x – 2y = 5.6
2x = y + 3.7
(–2.2, –0.6)
(–0.9, 1.9)
(0.3, –3.1)
(0.9, –1.9)

Question

Which is the best approximate solution of the system of equations? (Use the graphing calculator tool to graph the system. Round to the nearest tenth.)
–2x – 2y = 5.6
2x = y + 3.7    
(–2.2, –0.6)
(–0.9, 1.9)
(0.3, –3.1)
(0.9, –1.9)

Babyplier · Answer

@mercury

Mercury · Answer

it says to graph the system so I will take that approach

the first equation is in standard form, which makes it easy to find intercepts. to find the x-intercept, substitute y = 0 and solve for x. likewise, to find the y-intercept, substitute x = 0 and solve for y. 
once you have both intercepts, plot them both on the graph, then connect with a straight line

second equation is (almost) in y = mx + b form. flipping the left and right side of the equation gives us
  
y + 3.7 = 2x

then you can subtract 3.7 from both sides to get

y = 2x - 3.7

therefore, (0,-3.7) is the y-intercept, and it has a slope of 2. plot (0,-3.7), then go up 2 units and across 1 unit to get the next point. connect the two points with a straight line.

now, for the solution, simply estimate where the two graphs intersect and find the closest point from the answer choices