Solve 1200m^2=(20m+60m)*am/2

$$1200 m ^ { 2 } = \frac { ( 20 m + 60 m ) \cdot a m } { 2 }$$

Solve for a

$$\left\{\begin{matrix}\\a=30\text{, }&\text{unconditionally}\\a\in \mathrm{R}\text{, }&m=0\end{matrix}\right.$$

Steps for Solving Linear Equation

Multiply both sides of the equation by 2.

$$2400m^{2}=\left(20m+60m\right)am$$

Combine 20m and 60m to get 80m.

$$2400m^{2}=80mam$$

Multiply m and m to get m^{2}.

$$2400m^{2}=80m^{2}a$$

Swap sides so that all variable terms are on the left hand side.

$$80m^{2}a=2400m^{2}$$

Divide both sides by 80m^{2}.

$$\frac{80m^{2}a}{80m^{2}}=\frac{2400m^{2}}{80m^{2}}$$

Dividing by 80m^{2} undoes the multiplication by 80m^{2}.

$$a=\frac{2400m^{2}}{80m^{2}}$$

Divide 2400m^{2} by 80m^{2}.

$$a=30$$

Solve for m

$$\left\{\begin{matrix}\\m=0\text{, }&\text{unconditionally}\\m\in \mathrm{R}\text{, }&a=30\end{matrix}\right.$$