To solve the system of equations:
\begin{align*}4+168\times 10^3\times d_1+36\times 10^3\times d_2 & = -12 \quad (1) \-10+36\times 10^3\times d_1+72\times 10^3\times d_2 & = 0 \quad (2)\end{align*}
We can use the method of substitution to eliminate one variable and solve for the other.
Let's solve equation (2) for d_1:
-10 + 36\times 10^3 \times d_1 + 72\times 10^3\times d_2 = 0
Rearranging the equation, we have:
36\times 10^3 \times d_1 = 10 + 72\times 10^3\times d_2
Dividing both sides by 36\times 10^3, we get:
d_1 = \frac{10 + 72\times 10^3\times d_2}{36\times 10^3} \quad (3)
Substituting equation (3) into equation (1), we have:
4 + 168\times 10^3\times \left(\frac{10 + 72\times 10^3\times d_2}{36\times 10^3}\right) + 36\times 10^3\times d_2 = -12
Simplifying the equation, we get:
4 + \frac{168}{36}\times (10 + 72\times 10^3\times d_2) + 36\times 10^3\times d_2 = -12
Simplifying further, we have:
4 + \frac{4}{3}\times (10 + 72\times 10^3\times d_2) + 36\times 10^3\times d_2 = -12
Expanding and simplifying, we get:
4 + \frac{40}{3} + \frac{288}{3}\times 10^3\times d_2 + 36\times 10^3\times d_2 = -12
Combining like terms, we have:
\frac{128}{3}\times 10^3\times d_2 + 36\times 10^3\times d_2 = -12 - \frac{40}{3}
Simplifying further, we get:
\frac{164}{3}\times 10^3\times d_2 = -\frac{76}{3}
Dividing both sides by \frac{164}{3}\times 10^3, we have:
d_2 = -\frac{76}{3} \div \frac{164}{3}\times 10^3
Simplifying the division, we get:
d_2 = -\frac{76}{164}\times 10^3
Simplifying the fraction, we have:
d_2 = -\frac{19}{41}\times 10^3
Finally, we can substitute the value of d_2 into equation (3) to solve for d_1:
d_1 = \frac{10 + 72\times 10^3\times \left(-\frac{19}{41}\times 10^3\right)}{36\times 10^3}
Simplifying the equation, we get:
d_1 = \frac{10 - \frac{72\times 19}{41}}{36}
Simplifying the fraction, we have:
d_1 = \frac{10 - \frac{1368}{41}}{36}
Calculating the numerator and denominator separately, we have:
d_1 = \frac{410 - 1368}{36} = \frac{-958}{36} = -\frac{479}{18} \quad (4)
Therefore, the solution to the system of equations is d_1 = -\frac{479}{18} and d_2 = -\frac{19}{41}\times 10^3.
\textbf{Answer:} d_1 = -\frac{479}{18}, d_2 = -\frac{19}{41}\times 10^3