Solve 3x^2 -4x -7

Question

Factor the expression

(x + 1) (3 x - 7)

Evaluate

3 x^{2} - 4 x - 7

Rewrite the expression

3 x^{2} + (- 7 + 3) x - 7

Calculate

3 x^{2} - 7 x + 3 x - 7

Rewrite the expression

x \times 3 x - x \times 7 + 3 x - 7

Factor out x from the expression

x (3 x - 7) + 3 x - 7

Solution

(x + 1) (3 x - 7)

Show Solution

x_{1} = - 1, x_{2} = \frac{7}{3}

Alternative Form

x_{1} = - 1, x_{2} = 2. \dot{3}

Evaluate

3 x^{2} - 4 x - 7

To find the roots of the expression,set the expression equal to 0

3 x^{2} - 4 x - 7 = 0

Factor the expression

More Steps

Evaluate

3 x^{2} - 4 x - 7

Rewrite the expression

3 x^{2} + (- 7 + 3) x - 7

Calculate

3 x^{2} - 7 x + 3 x - 7

Rewrite the expression

x \times 3 x - x \times 7 + 3 x - 7

Factor out x from the expression

x (3 x - 7) + 3 x - 7

Factor out 3 x - 7 from the expression

(x + 1) (3 x - 7)

(x + 1) (3 x - 7) = 0

When the product of factors equals 0,at least one factor is 0

x + 1 = 0 3 x - 7 = 0

Solve the equation for x

More Steps

Evaluate

x + 1 = 0

Move the constant to the right-hand side and change its sign

x = 0 - 1

Removing 0 doesn't change the value,so remove it from the expression

x = - 1

x = - 1 3 x - 7 = 0

Solve the equation for x

More Steps

Evaluate

3 x - 7 = 0

Move the constant to the right-hand side and change its sign

3 x = 0 + 7

Removing 0 doesn't change the value,so remove it from the expression

3 x = 7

Divide both sides

\frac{3 x}{3} = \frac{7}{3}

Divide the numbers

x = \frac{7}{3}

x = - 1 x = \frac{7}{3}

Solution

x_{1} = - 1, x_{2} = \frac{7}{3}

Alternative Form

x_{1} = - 1, x_{2} = 2. \dot{3}

Show Solution