You're likely to encounter a question or two on the GED Mathematical Reasoning test that present mathematical relationships in graph form. These questions will require you to understand the relationships between slopes, linear equations, and coordinate planes.
The following practice questions ask you to find the equation of a line based on its slope and y-intercept, and then to indicate where a circle intersects the negative y-axis on a plotted graph.
Practice questions
What is the equation of a line with slope 0.75 and y-intercept 6 if you express the slope as a rational number?
A. 3x – 4y = 24
B. 4x – 3y + 24 = 0
C. 3x + 4y = –24
D. 3x – 4y + 24 = 0
A circle is drawn with its center at the origin and a radius of 5 units. Where will the circumference intersect the negative y-axis? Circle this point on the graph.
Answers and explanations
D.
Using the general equation of a line y = mx + b and substituting the given values, you would arrive at
(0, –5)
The circumference would intersect the negative y-axis at a point 5 units below the origin, or at (0, –5) since the y-axis goes from top to bottom.