The line with equation is translated upwards by 4 units. What is the -intercept of the resulting line?
Solution
The line with equation has slope 2. When this line is translated, the slope does not change. The line with equation has -intercept -6. When this line is translated upwards by 4 units, its -intercept is translated upwards by 4 units and so becomes -2. This means that the new line has equation . To find its -intercept, we set to obtain and so or . Thus, the -intercept is 1.
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