Moises is determining the solution to the system of equations that is show below. Equation representing line A: y = one-third x
+ 1 Points on line B: (3, –12) and (9, –24) Step 1: Determine the slope for B: StartFraction negative 24 minus (negative 12) Over 9 minus 3 EndFraction = StartFraction negative 12 Over 6 EndFraction = negative 2. Step 2: Determine the y-intercept for B: 3 = negative 2 (negative 12) + b. 3 = 24 + b. Negative 21 = b. Step 3: Write the equation in slope-intercept form: y = negative 2 x minus 21 Step 4: Graph the equations: On a coordinate plane, a line goes through (negative 3, 0) and (6, 3) and another line goes through (negative 9, negative 3) and (negative 6, negative 9). Step 5: Determine the intersection point: approximately (–9, –2) Which best describes Moises’ error? Moises incorrectly determined the slope of the line. Moises incorrectly determined the y-intercept of the line. Moises incorrectly graphed one or both of the stated equations. Moises incorrectly approximated the point of intersection shown on the graph.
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