Question

Below, four equations are given. Three are equivalent, which equation is NOT equivalent to the others?

A. y - 6 = -3/5(x + 5)
B. y + 5 = -3/5(x - 6)
C. 3x + 5y = 15
D. y = -3/5x + 3

Answer 1

Answer: B

Explanation:

Let's convert all of the equations into slope-intercept form:

`y = mx + b`

A:

`y - 6 = (-3)/(5)(x + 5)`

`y = (-3)/(5)(x + 5) + 6`

`y = (-3)/(5)x - 3 + 6`

`y = (-3)/(5)x + 3`

B:

`y + 5 = (-3)/(5)(x - 6)`

`y = (-3)/(5)(x - 6) - 5`

`y = (-3)/(5)x + (18)/(5) - 5`

`y = (-3)/(5)x - (7)/(5)`

Since D is already equal to A, and B is not equal to either of these, we can skip reducing down C and say that B is not like the others.

But in case you're interested:

C:

`3x + 5y = 15`

`5y = -3x + 15`

`y = (-3)/(5)x + 3`