Question

solve 3 X square + 17 x minus 20 is equal to zero​

Answer 1

ANSWER:

• Value of x is 1 or -20/3

GIVEN:

• 3x²+17x-20 = 0

TO FIND:

• Simplify and find the value of x.

SOLUTION:

=> 3x²+17x-20 = 0

=> 3x²+20x-3x-20 = 0

=> (3x²-3x)+(20x-20) = 0

=> 3x(x-1)+20(x-1) = 0

=> (x-1)(3x+20) = 0

Either (x-1) = 0

=> x = 1

Either (3x+20) = 0

=> 3x = -20

=> x = -20/3

NOTE:

Some important formulas:

(a+b)² = a²+b²+2ab

(a-b)² = a²+b²-2ab

(a+b)(a-b) = a²-b²

(a+b)³ = a³+b³+3ab(a+b)

(a-b)³ = a³-b³-3ab(a-b)

a³+b³ = (a+b)(a²+b²-ab)

a³-b³ = (a-b)(a²+b²+ab)

(a+b)² = (a-b)²+4ab

(a-b)² = (a+b)²-4ab

Answer 2

$Given \: quadratic \: equation : \\3x^{2} + 17x - 20 = 0$

/* Splitting the middle term ,we get */

$\implies 3x^{2} + 20x - 3x - 20 = 0$

$\implies x( 3x + 20 ) - 1( 3x + 20 ) = 0$

$\implies (3x + 20)( x - 1 ) = 0$

$\implies 3x + 20 = 0 \: Or \: x - 1 = 0$

$\implies 3x = - 20 \: Or \: x = 1$

$\implies x = \frac{- 20}{3} \: Or \: x = 1$

Therefore.,

$\green { x = \frac{- 20}{3} \: Or \: x = 1 }$

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