Choose the equation that represents a line that passes through points (−1, 2) and (3, 1).

4x − y = −6
x + 4y = 7
x − 4y = −9
4x + y = 2

the difference of two squares is a special form that has a factorization worth memorizing.

a² - b² = (a - b)(a + b)

your equation can be factored as

x² - 16 = 0

(x - 4)(x + 4) = 0

the zero product rule tells you the solutions are the values of x that make these factors zero: x=4, x=-4.

any line whose slope not equal to -4 does not satisfy these requirements.

step-by-step explanation:

going from (1,2) to (3, -6), x increases by 2 and y decreases by 8.   thus, the slope of a line thru those two points has the slope m = -8/2, or   m = -4.

thus, no line that has a slope different from m = -4 could be appropriate.