Question

expand by formula : (x + 3) (x – 7)​

Answer 1

Answer:

x^2 - 4x - 21

Step-by-step explanation:

(x + 3) (x - 7)

(x + a) (x - b) = x^2 + (a - b)x - ab

(x + 3) (x - 7) = (x)^2 + (3 - 7)x - (3 * 7)

Therefore, (x + 3) (x - 7) = x^2 - 4x - 21