Question

What is the equation of a line with a slope of 7 and a point (1, 8) on the line?

Answer 1

ANSWER

The required equation is

$y = 7 x+ 1$

EXPLANATION

Let the equation of the line be

$y = mx + b...(1)$
where
$m = 7$
is the slope of the line. We substitute this value of the slope into the equation (1) to obtain,


$y = 7x + b...(2)$


Since the point (1,8) lies on the line, it must satisfy this equation.



We substitute the x and y value of the point into the equation(2) to get,

$8 = 7(1) + b$

This simplifies to give us,

$8=7+b$


We solve for b to get,

$b = 8 - 7$

$b = 1$


We substitute the value of b back into equation (2) to get


$y = 7x + 1$

Answer 2

8=m+7

m=1

so

y=x+7

that is the equasion