Question

using the identity find a)(¾m+⅔n) (¾m-⅔) , b)983²-17², c)194x206

Answer 1

Formula:

(a + b)(a - b) = a² - b²

Question a:

(3/4 m + 2/3 n) (3/4 m - 2/3n) = (3/4 m)² - (2/3 n)²

(3/4 m + 2/3 n) (3/4 m - 2/3n) = 9/16 m² - 4/9 n²

Question b:

983²- 17² = (983 + 17) (983 - 17)

983²- 17² = (1000) (966)

983²- 17² = 966000

Question c:

194 x 206 = (200 - 6)(200 + 6)

194 x 206 = (200)² - (6)²

194 x 206 = 40000 - 36

194 x 206 = 39964