You 2l x 2w and blah blah blah blah blah blah blah blah
ANSWER

EXPLANATION
The given expression is

To find an expression for d in terms of a, b, and c, means we want to make d the subject of the relation.
This means that, we need to isolate d on one side of the equation while all other terms are on the other side.
We subtract from both sides of the equation to obtain,

We now divide through by -1, to get,

Or

The topic is change of subject
Answer:
x = 3
, y = 5
Step-by-step explanation:
Solve the following system:
{3 y - 7 x = -6 | (equation 1)
3 y - 3 x = 6 | (equation 2)
Subtract 3/7 × (equation 1) from equation 2:
{-(7 x) + 3 y = -6 | (equation 1)
0 x+(12 y)/7 = 60/7 | (equation 2)
Multiply equation 2 by 7/12:
{-(7 x) + 3 y = -6 | (equation 1)
0 x+y = 5 | (equation 2)
Subtract 3 × (equation 2) from equation 1:
{-(7 x)+0 y = -21 | (equation 1)
0 x+y = 5 | (equation 2)
Divide equation 1 by -7:
{x+0 y = 3 | (equation 1)
0 x+y = 5 | (equation 2)
Collect results:
Answer: {x = 3
, y = 5