If 4x−5y=−37 and 7x+y=−16, then x−y=________.
- A-8
- B8
- C2
- D-2
Solution & Step-by-step Explanation
Given equations:
4x−5y=−37
7x+y=−16⟹y=−16−7x
Substitute the value of y from equation (2) into equation (1):
4x−5(−16−7x)=−37
4x+80+35x=−37
39x+80=−37
39x=−37−80
39x=−117
x=−3
Now substitute x=−3 back into the expression for y:
y=−16−7(−3)=−16+21=5
Find the value of x−y:
x−y=−3−5=−8
4x−5y=−37
7x+y=−16⟹y=−16−7x
Substitute the value of y from equation (2) into equation (1):
4x−5(−16−7x)=−37
4x+80+35x=−37
39x+80=−37
39x=−37−80
39x=−117
x=−3
Now substitute x=−3 back into the expression for y:
y=−16−7(−3)=−16+21=5
Find the value of x−y:
x−y=−3−5=−8