Question

A line passes through the point A(n,4) and B(8,6) and is parallel to y=2x-5. what is the value of n

Answer 1

The slope-intercept form:

y = mx + b

m - slope

b - y-intercept

We have the line y = 2x - 5.

The parallel lines have the same slope. Therefore we have y = 2x + b.

Put the coordinates of the point B(8, 6) to the equation:

6 = 2(8) + b

6 = 16 + b     subtract 16 from both sides

-10 = b → b = -10

The equation of a line: y = 2x - 10.

Put the coordinates of the point A(n, 4) to the equation:

4 = 2(n) - 10     add 10 to both sides

14 = 2n     divide both sides by 2

7 = n → n = 7