Question

If the point (K,-5) lies on the line whose equation is 3x + y = 7, then the value of K is

Answer 1

K = 4

Explanation:

The x-y point ( K, -5 ) means that ...

x = K and y = -5

Let's plug in K and -5 for y in the equation to find the value of K (which is the same as x).

3(K) + (-5) = 7

3K - 5 = 7

3K = 7 + 5

3K = 12

K = 4