Finding Angle Between Lines Passing Through Points (-2,-1) and (4,1)

AI Thread Summary
To find the equation of a line passing through (2,3) and inclined at 30 degrees to the positive x-axis, the gradient is determined using the tangent function, resulting in a slope of approximately 0.577. The equation can be expressed as y = 0.577x + c, where c is calculated using the point (2,3). However, there is confusion regarding the calculation of c, as substituting (2,3) does not yield the correct result. Additionally, the discussion clarifies that the angle should be measured in degrees, not Celsius. The conversation emphasizes the importance of correctly applying trigonometric functions to find the slope and equation of the line.
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Homework Statement



Find the equation of a straight line which passes through the point (2,3) and is inclined at 30 Celsius to the positive direction of the x-axis.

The Attempt at a Solution


i have no idea how to to this question as i was away for a week of school >< and my teacher gave my catch up worksheets. I am falling behind class. so need help

Homework Statement


find the angle between the straight line 3x-2y=4 and the line joining the points (-2,-1) and (4,1)

please guide me step by step

thanks
 
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What you need for the first one is a point on the line (which you were given) and the gradient.
This will help you to get the gradient:

Tan(angle the line makes with the +ve x-axis)=gradient of the line.

EDIT: I think you mean 30 degrees and not celsius as that implies a temperature.
 
Last edited:
rock.freak667 said:
What you need for the first one is a point on the line (which you were given) and the gradient.
This will help you to get the gradient:

Tan(angle the line makes with the +ve x-axis)=gradient of the line.

EDIT: I think you mean 30 degrees and not celsius as that implies a temperature.

so y=mx+c
Tan(30degrees) is m =0.56
so y=0.56x+c

find c, sub (2,3)

y=0.56x+1.85 ?
 
(0.56)(2)+ 1.85= 1.12+ 1.85= 2.97, not 3. Did you mean tan(30)= 0.58?
 

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