Question

Pmlease helppp tyyyy

Answer 1

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 = (-b \± √(D))/(2a)}\\\\`

`\sf = (-[-6] \± √(76))/(2*5)\\\\= (6 \±8.7)/(10)\\\\=(6+8.7)/(10) \ ; \ or \ x =(6-8.7)/(10)\\\\=(14.7)/(10) \ ; \ or \ x = (-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