Solve 5(x-7) 4x = 1

Question

Solve the quadratic equation

Solve using the quadratic formula

Solve by completing the square

Solve using the PQ formula

x_{1} = \frac{35 - 1230}{10}, x_{2} = \frac{35 + 1230}{10}

Alternative Form

x_{1} \approx - 0.007136, x_{2} \approx 7.007136

Evaluate

5 (x - 7) \times 4 x = 1

Multiply

More Steps

20 x (x - 7) = 1

Expand the expression

More Steps

20 x^{2} - 140 x = 1

Move the expression to the left side

20 x^{2} - 140 x - 1 = 0

Substitute a= 20,b= - 140 and c= - 1 into the quadratic formula x = \frac{- b \pm b ^{2} - 4 a c}{2 a}

x = \frac{140 \pm ( - 140 ) ^{2} - 4 \times 20 ( - 1 )}{2 \times 20}

Simplify the expression

x = \frac{140 \pm ( - 140 ) ^{2} - 4 \times 20 ( - 1 )}{40}

Simplify the expression

More Steps

x = \frac{140 \pm 19680}{40}

Simplify the radical expression

More Steps

x = \frac{140 \pm 4 1230}{40}

Separate the equation into 2 possible cases

x = \frac{140 + 4 1230}{40} x = \frac{140 - 4 1230}{40}

Simplify the expression

More Steps

x = \frac{35 + 1230}{10} x = \frac{140 - 4 1230}{40}

Simplify the expression

More Steps

x = \frac{35 + 1230}{10} x = \frac{35 - 1230}{10}

Solution

x_{1} = \frac{35 - 1230}{10}, x_{2} = \frac{35 + 1230}{10}

Alternative Form

x_{1} \approx - 0.007136, x_{2} \approx 7.007136

Show Solution