How do you evaluate $2c+3a$ if $a=3$ and $c=6$?

Hint: We have the equation of $2c+3a$. We also have the values for the terms $a=3$ and $c=6$. We place the values and complete the multiplications. Then we apply the binary operation of addition to find the final solution.

Complete step by step solution:
The given equation $2c+3a$ is a linear equation of two variables. We need to simplify the equation by putting the particular value given for the variables.
It is given that $a=3$ and $c=6$ for the equation $2c+3a$.
We break the multiplication by multiplying 2 with 6 and 3 with 3.
So, $2\times 6=12$ and $3\times 3=9$.
The equation becomes $2c+3a=2\times 6+3\times 3$.
We place the values on one side and get
$
\Rightarrow 2c+3a \\
\Rightarrow2\times 6+3\times 3 \\
 =12+9 \\
$
Now we take the constants.
There are two such constants which are $12,9$.
The binary operation between them is addition which gives us $12+9=21$.
The final solution becomes
$2c+3a=12+9=21$.
The solution for $2c+3a$ is 21 for $a=3$ and $c=6$.

Therefore, the solution is 21.

Note: We can also take from the equation $2c+3a=2\times 6+3\times 3$.
We take 3 common terms and get $2c+3a=2\times 6+3\times 3=3\left( 2\times 2+3 \right)$.
We complete the multiplication of $2\times 2=4$. Then we have $\left( 2\times 2+3 \right)=4=3=7$.
Then we have multiplication of 7 with 3 which gives $3\times 7=21$.
Therefore, the final solution becomes 21.