Question

find the zeros of the following polynomial
4x² -17x -21
please solve !!!​

Answer 1

Hey mate hope it helps you...

4x² - 21x + 4x - 21 = 0

4x ( x + 1) - 21(x+1) = 0

(4x - 21)(x + 1) = 0

x = 21/4 or -1

Answer 2

Answer:

-1, 21/4.

Step-by-step explanation:

4x² - 17x - 21.

To find zeroes equate it to zero.

i.e 4x² - 17x - 21 = 0,

By middle term factorisation method,

4x² - 21x + 4x - 21 = 0

⇒ x(4x - 21) + 1(4x - 21) = 0

⇒(x + 1)(4x - 21) = 0

∴ x = -1 or x = 21/4.