Line passes through the point and is perpendicular to the line . At what -coordinate does intersect the line ?
Answer and explanation
Correct answer: D.
- uses a positive slope instead of the negative reciprocal .
- drops the negative sign from the correct coordinate .
- subtracts from instead of adding to both sides.
- drops the negative sign from the correct coordinate .
- subtracts from instead of adding to both sides.
- Step 1: Determine the slope of : , so . The perpendicular line has slope .
- Step 2: Write the point-slope form for line passing through : .
- Step 3: Substitute to find the intersection -coordinate: .
Answer
-\frac{5}{2}.
Practise more Lines and slope.
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