# How do you write an equation of a line going through (1,7) parallel to the x-axis?

Sep 7, 2016

$y = 7$

#### Explanation:

The equation of the x-axis is $y = 0$, or $y = 0 x + 0$. The slope is therefore $0$.

We want the equation of a line parallel to this one. Parallel lines mean equal slopes, so by point-slope form we have:

$y - {y}_{1} = m \left(x - {x}_{1}\right)$

$y - 7 = 0 \left(x - 1\right)$

$y - 7 = 0 x - 0$

$y = 7$

Hence, the equation of the line is $y = 7$.

Hopefully this helps!

Sep 7, 2016

$y = 7$

#### Explanation:

The x-axis is a horizontal line. It has a slope of 0.

Any line parallel to the x-axis is therefore also horizontal and has a slope = 0.

The equation of any horizontal line is $y = \text{a number}$

The number is the y-intercept, and it stays the same, regardless of which value of x is used.

The point #(1,7) means that the y-value is 7, the line will also go through 7 on the y-axis, therefore this gives us the y -intercept,

Now we have: $m = 0 \mathmr{and} c = 7$

$y = 7$