<span>Equation A: 4c = d − 8
</span><span>Equation B: c = 5d + 8
</span>
Multiply Equation A by -5:
Equation A: - 20c = -5d + 40
Equation (1) + (2) :
-19c = 48
Answer: <span>B. Multiply equation A by -5</span>
Basically you know that the 2 wholes from both sides cancel out.
Set up the equation, 5/8 = 3/12 + 3/x
3/x = 5/8 - 3/12
Set them to have a common denominator, 3/x = 15/24 - 6/24
3/x = 9/24
Simplify 9/24 and you will get 3/8
3/x = 3/8
Obviously this means x = 8
Answer: c the x-and y-coordinates are switched
