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Find the equation of the straight line which passes through the point (2,3) and is

inclined at 30° to the positive direction of the x-axis.

1 Answer

8 votes

Answer: y = 1.73*x - 0.46

Explanation:

For a linear equation of the form:

y = a*x + b

Where a is the slope and b is the y-intercept.

If we have an angle of A degrees with respect to the x-axis, the slope of the function can be calculated as:

Tan(A) = a.

in this case, we have we have an inclination of 30° to the positive x-axis (measured from the positive y-axis) and we know that the angle between the positive x-axis and the positive y-axis is 90°, then the angle measured from the positive axis will be such that:

A + 30° = 90

A = 90° - 30° = 60°

Then the slope is:

a = Tan(60°) = 1.73

Then we have the equation:

y = 1.73*x + b

And we know that this line passes through the point (2, 3) then we can replace x by 2 and y by 3 in the equation, and find the value of b.

3 = 1.73*2 + b

3 - 1.73*2 = b = -0.46

Then the equation is:

y = 1.73*x - 0.46

User Deadkarma
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