Question

hey guys plz help mee I need ur help..plz solve this​

Answer 1

Working out:

So let's complete the activity at once.

a) Solve by using formula :

• 3m² + 2m - 7 = 0

Solution : 3m² + 2m - 7 = 0

Comparing with ax² + bx + c = 0

• a = 3, b = 2 and c = -7

Hence, b² - 4ac = ?

Just plug the values of a, b and c from the equation,

⇛ b² - 4ac = 2² - 4(3)(-7)

⇛ b² - 4ac = 4 - (-84)

⇛ b² - 4ac = 4 + 84

⇛ b² - 4ac = 88

Now using Discriminant formula,

$\sf{ \longrightarrow{m = \dfrac{ - b \pm \sqrt{ {b}^{2} - 4ac } }{2a} }}$

Again the plug the values of b, a and b² - 4ac

$\sf{ \longrightarrow{m = \dfrac{ - 2 \pm \sqrt{88} }{2 \times 3} }}$

$\sf{ \longrightarrow{m = \dfrac{ - 2 \pm 2 \sqrt{22} }{6} }}$

$\sf{ \longrightarrow{m = \dfrac{ - 1 \pm \sqrt{22} }{3} }}$

On solving the value of m will be,

$\sf{ \longrightarrow{m = \dfrac{ - 1 + \sqrt{22} }{3} \: or \: \dfrac{ - 1 - \sqrt{22} }{3} }}$

And we are done !!