Question

find k
81y² -k = (9y +½) × (9y-½)​

Answer 1

Answer:

81y^2 - k = (9y)^2 - (1/2)^2

81y^2 - k = 81y^2 - 1/4

-k = -1/4

k = 1/4

Answer 2

k=1/4

Step-by-step explanation:

81y²-k=(9y+1/2)(9y-1/2)

81y²-k=(9y)²-(1/2)²

81y²-k=81y²-1/4

-k=-1/4

Therefore, k=1/4