Answer:
That depends on which operations you want to do first. The order of operations affect to outcome of the equation.
In this case:
15 - (3 x 4) + 9 = 12
times the length by width and you will get your answer use a calculator that will be the answer
First Equation:

Second Equation can be written as:

Slope of first equation is -3/4 and slope of second equation is 3/4.
Slope of parallel lines must be equal, and slope of perpendicular lines are the negative reciprocal of each other. None of these conditions can be seen for given two equations.
So, the two lines are neither parallel nor perpendicular.
So correct option is C
17.6 is your answer
Hope this helps!!
(820*7)-(480*7)=? This is how to solve the equation