Question

Find the sum and product of zeroes of each of the polynomials (25 - 26):
25. 5x2 - 7x + 2
26. 3x2 - 4x - 4​

Answer 1

Answer:

(25). 1.4 and 0.4 (26). - 1 $\frac{1}{3}$ and 1 $\frac{1}{3}$

Step-by-step explanation:

25). 5x² - 7x + 2 = 0

D = (-7)² - 4×5×2 = 9

$x_{12}$ = (- (-7) ± √9) / 2×5 = (7 ± 3) / 10

$x_{1}$ = $\frac{10}{10}$ = 1

$x_{2}$ = $\frac{4}{10}$ = $\frac{2}{5}$ = 0.4

$x_{1}$ + $x_{2}$ = 1.4

$x_{1}$ × $x_{2}$ = 0.4

26). 3x² - 4x - 4 = 0

D = (- 4)² - 4×(- 4)×3 = 64

$x_{12}$ = (- (- 4) ± √64) / 2×3 = (4 ± 8) / 6

$x_{1}$ = 2

$x_{2}$ = - $\frac{2}{3}$

$x_{1}$ + $x_{2}$ = 1 $\frac{1}{3}$

$x_{1}$ × $x_{2}$ = - 1 $\frac{1}{3}$