Solve 2x^2-13x-7 - ScanMath

Question

Factor the expression

(x - 7) (2 x + 1)

Evaluate

2 x^{2} - 13 x - 7

Rewrite the expression

2 x^{2} + (1 - 14) x - 7

Calculate

2 x^{2} + x - 14 x - 7

Rewrite the expression

x \times 2 x + x - 7 \times 2 x - 7

Factor out x from the expression

x (2 x + 1) - 7 \times 2 x - 7

Factor out - 7 from the expression

x (2 x + 1) - 7 (2 x + 1)

Solution

(x - 7) (2 x + 1)

Show Solution

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

Alternative Form

x_{1} = - 0.5, x_{2} = 7

Evaluate

2 x^{2} - 13 x - 7

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

2 x^{2} - 13 x - 7 = 0

Factor the expression

More Steps

Evaluate

2 x^{2} - 13 x - 7

Rewrite the expression

2 x^{2} + (1 - 14) x - 7

Calculate

2 x^{2} + x - 14 x - 7

Rewrite the expression

x \times 2 x + x - 7 \times 2 x - 7

Factor out x from the expression

x (2 x + 1) - 7 \times 2 x - 7

Factor out - 7 from the expression

x (2 x + 1) - 7 (2 x + 1)

Factor out 2 x + 1 from the expression

(x - 7) (2 x + 1)

(x - 7) (2 x + 1) = 0

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

x - 7 = 0 2 x + 1 = 0

Solve the equation for x

More Steps

Evaluate

x - 7 = 0

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

x = 0 + 7

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

x = 7

x = 7 2 x + 1 = 0

Solve the equation for x

More Steps

Evaluate

2 x + 1 = 0

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

2 x = 0 - 1

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

2 x = - 1

Divide both sides

\frac{2 x}{2} = \frac{- 1}{2}

Divide the numbers

x = \frac{- 1}{2}

Use \frac{- a}{b} = \frac{a}{- b} = - \frac{a}{b} to rewrite the fraction

x = - \frac{1}{2}

x = 7 x = - \frac{1}{2}

Solution

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

Alternative Form

x_{1} = - 0.5, x_{2} = 7

Show Solution