Solve v^2=2*0.4(1.25+1.5)

$$v ^ { 2 } = 2 \times 0.4 ( 1.25 + 1.5 )$$

Solve for v

$$v = \frac{\sqrt{55}}{5} \approx 1.483239697$$

$$v = -\frac{\sqrt{55}}{5} \approx -1.483239697$$

Steps by Finding Square Root

Multiply 2 and 0.4 to get 0.8.

$$v^{2}=0.8\left(1.25+1.5\right)$$

Add 1.25 and 1.5 to get 2.75.

$$v^{2}=0.8\times 2.75$$

Multiply 0.8 and 2.75 to get 2.2.

$$v^{2}=2.2$$

Take the square root of both sides of the equation.

$$v=\frac{\sqrt{55}}{5} v=-\frac{\sqrt{55}}{5}$$

Steps Using the Quadratic Formula

Multiply 2 and 0.4 to get 0.8.

$$v^{2}=0.8\left(1.25+1.5\right)$$

Add 1.25 and 1.5 to get 2.75.

$$v^{2}=0.8\times 2.75$$

Multiply 0.8 and 2.75 to get 2.2.

$$v^{2}=2.2$$

Subtract 2.2 from both sides.

$$v^{2}-2.2=0$$

This equation is in standard form: ax^{2}+bx+c=0. Substitute 1 for a, 0 for b, and -2.2 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.

$$v=\frac{0±\sqrt{0^{2}-4\left(-2.2\right)}}{2}$$

Square 0.

$$v=\frac{0±\sqrt{-4\left(-2.2\right)}}{2}$$

Multiply -4 times -2.2.

$$v=\frac{0±\sqrt{8.8}}{2}$$

Take the square root of 8.8.

$$v=\frac{0±\frac{2\sqrt{55}}{5}}{2}$$

Now solve the equation v=\frac{0±\frac{2\sqrt{55}}{5}}{2} when ± is plus.

$$v=\frac{\sqrt{55}}{5}$$

Now solve the equation v=\frac{0±\frac{2\sqrt{55}}{5}}{2} when ± is minus.

$$v=-\frac{\sqrt{55}}{5}$$

The equation is now solved.

$$v=\frac{\sqrt{55}}{5} v=-\frac{\sqrt{55}}{5}$$