Question

How do you find x given (2 , 4) , (x , 8) and the slope is -2 ?

Answer 1

Hint: The slope of a line segment joining the points ( a ,b) and ( x , y) is equal to $\dfrac{b-y}{a-x}$ where (a , b) and (x , y) are 2 different points. Using this formula we can find the value of x.

Complete step-by-step answer:
The given points are (2, 4) and (x , 8) and the slope is -2
We know that the formula for slope of line joint to points $\dfrac{b-y}{a-x}$ where (a , b) and (x , y) are 2 different points
So we can say slope of line joining (2, 4) and (x , 8) is equal to $\dfrac{8-4}{x-2}$ which is equal to -2
So $\dfrac{4}{x-2}=-2$
By multiplying x – 2 both sides we get
$\Rightarrow 4=4-2x$
So 2x is equal to 0 that means x is equal to 0.

Note: While solving the question by above method keep in mind that 2 given points are different if both points are same then we can not find the slope. If there x coordinates are the same y coordinates are different then slope will be tending to infinity. We can solve the given equation in different methods , we have a given point (2 , 4) and slope -2 so we can find the equation of the line . The variable point (x , 8) will satisfy the equation of line. So we can find the value of x.