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# The angle between the positive horizontal axis and a given line is 135o. Find th...

### Question

The angle between the positive horizontal axis and a given line is 135o. Find the equation of the line if it passes through the point (2,3)

A) x - y = 1

B) x + y = 1

C) x + y = 5

D) x - y = 5

### Explanation:

m = tan 135o = -tan 45o = -1
$$\frac{y - y_1}{x - x_1}$$ = m
$$\frac{y - 3}{x - 2}$$ = -1
= y - 3 = -(x - 2)
= -x + 2
x + y = 5

## Dicussion (1)

• m = tan 135o = -tan 45o = -1
$$\frac{y - y_1}{x - x_1}$$ = m
$$\frac{y - 3}{x - 2}$$ = -1
= y - 3 = -(x - 2)
= -x + 2
x + y = 5