Solve 200(t-10)+500*0.12*(t-140)=0

$$200 ( t - 10 ) + 500 \times 0.12 \times ( t - 140 ) = 0$$

Solve for t

$$t=40$$

Steps for Solving Linear Equation

Use the distributive property to multiply 200 by t-10.

$$200t-2000+500\times 0.12\left(t-140\right)=0$$

Multiply 500 and 0.12 to get 60.

$$200t-2000+60\left(t-140\right)=0$$

Use the distributive property to multiply 60 by t-140.

$$200t-2000+60t-8400=0$$

Combine 200t and 60t to get 260t.

$$260t-2000-8400=0$$

Subtract 8400 from -2000 to get -10400.

$$260t-10400=0$$

Add 10400 to both sides. Anything plus zero gives itself.

$$260t=10400$$

Divide both sides by 260.

$$t=\frac{10400}{260}$$

Divide 10400 by 260 to get 40.

$$t=40$$