Solve u(x)=20x^2-9x+1=20x^2-5x-4x+1

$$u ( x ) = 20 x ^ { 2 } - 9 x + 1 = 20 x ^ { 2 } - 5 x - 4 x + 1$$

Solve for x (complex solution)

$$x\in \mathrm{C}$$

Solution Steps

Combine -5x and -4x to get -9x.

$$20x^{2}-9x+1=20x^{2}-9x+1$$

Subtract 20x^{2} from both sides.

$$20x^{2}-9x+1-20x^{2}=-9x+1$$

Combine 20x^{2} and -20x^{2} to get 0.

$$-9x+1=-9x+1$$

Add 9x to both sides.

$$-9x+1+9x=1$$

Combine -9x and 9x to get 0.

$$1=1$$

Compare 1 and 1.

$$\text{true}$$

This is true for any x.

$$x\in \mathrm{C}$$

Solve for x

$$x\in \mathrm{R}$$

Solution Steps

Combine -5x and -4x to get -9x.

$$20x^{2}-9x+1=20x^{2}-9x+1$$

Subtract 20x^{2} from both sides.

$$20x^{2}-9x+1-20x^{2}=-9x+1$$

Combine 20x^{2} and -20x^{2} to get 0.

$$-9x+1=-9x+1$$

Add 9x to both sides.

$$-9x+1+9x=1$$

Combine -9x and 9x to get 0.

$$1=1$$

Compare 1 and 1.

$$\text{true}$$

This is true for any x.

$$x\in \mathrm{R}$$