Question

Explain how to use factoring to solve the equation: 2x^2 + 5x = 3..

Answer 1

Answer: 1/2 or -3

Explanation:

2x2+5x=3

Bring 3 to the other side

2x2+5x-3=0

Factorise

Factors of -6 that will give +5= +6 &-1

2x2+6x-x-3=0

2x(x+3)-1(x+3)=0

(2x-1)(x+3)=0

2x-1=0

2x=1

X=1/2 or

X+3=0

X= -3

Therefore

X=1/2 or -3

Answer 2

x = 1/2 x=-3

Explanation:

2x^2 + 5x = 3

Subtract 3 from each side

2x^2 + 5x - 3 = 3-3

2x^2 + 5x -3=0

(2x )(x )

Since we need to multiply to -3, the factors are

-1,3 or 1.-3

We need to add to 5

We will want to multiply the 2 and 3 and this will need to be positive

(2x ) (x + 3 )

The 1 will be negative

(2x -1 ) (x + 3 ) =0

Using the zero product property

(2x -1 ) =0 (x + 3 ) =0

2x-1+1=0+1 x+3-3=0-3

2x =1 x=-3

x = 1/2 x=-3