SOLUTION: (1)By looking at a linear equation, how can you tell if the corresponding line is parallel to the x-axis? (2)By looking at a linear equation, how can you tell if the line forms

Algebra ->  Linear-equations -> SOLUTION: (1)By looking at a linear equation, how can you tell if the corresponding line is parallel to the x-axis? (2)By looking at a linear equation, how can you tell if the line forms       Log On


   

Question 247583: (1)By looking at a linear equation, how can you tell if the corresponding line is parallel to the x-axis?
(2)By looking at a linear equation, how can you tell if the line forms a 45-degree angle with the x-axis?
Answer by oberobic(2304) About Me  (Show Source):
You can put this solution on YOUR website!
(1) A horizontal line will be parallel to the x-axis. Since the slope = change in y / change in x, we see that the slope = 0. So y = a number is parallel to the x-axis and is a horizontal line.
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graph%28500%2C500%2C-10%2C10%2C-10%2C10%2C3%29graph of y=3
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(2) With a 45-degree angle, x and y change at the same rate. That is, a 45-degree angle cuts a 90-degree angle in half. Imagining how it looks on graph, when we have a change in y of 1, we have a change in x of 1, etc. So the slope is 1. When we have an equation where the coefficient of x is 1, we have a 45-degree angle.
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graph%28500%2C500%2C-10%2C10%2C-10%2C10%2Cx%29graph of y=x