Question

Pmlease helppp tyyyy

Answer 1

Answer:

Step-by-step explanation:

Solving quadratic equation using formula:

 5x² - 6x - 2 = 0

a = Coefficient of x² = 5

b = coefficient of x = -6

c = constant = -2

Discriminant = D = b² - 4ac

                           = (-6)² - 4 * 5 * (-2)

                           = 36 +  40

                           = 76  > 0

So, the quadratic equation has two distinct real roots.

$\sf \boxed{\bf x = \dfrac{-b \± \sqrt{D}}{2a}}$

     $\sf = \dfrac{-[-6] \± \sqrt{76}}{2*5}\\\\= \dfrac{6 \±8.7}{10}\\\\=\dfrac{6+8.7}{10} \ ; \ or \ x =\dfrac{6-8.7}{10}\\\\=\dfrac{14.7}{10} \ ; \ or \ x = \dfrac{-2.7}{10}$

x = 1.47  or x = -0.27

Answer: x = 1.5 or (-0.3)

b) x² + 3x = 40

x² + 3x - 40= 0

We can solve the quadratic equation using factor method.

Sum = 3

Product = -40

Factors = 8 , (-5)

 When we add, 8 + (-5) = 3 , we get 5and when we multiply 8 *(-5) = -40, we get -(-40).

Rewrite the middle term of the quadratic equation using the factors.

 x² + 8x - 5x - 40 = 0

x(x + 8) - 5(x + 8)= 0

 (x + 8) (x - 5)    = 0

 x + 8 = 0   or x - 5 = 0

     x = -8   or       x = 5

Answer : x = -8 , 5