Answer: B
Step-by-step explanation:
Let's solve the given equation. Then we can see which other equation has the same answer.
-5n+31=-14n-5
36=-9n
n=-4
We need to fina another equation that gives n=4 as the answer.
A. Incorrect
3-6n+3n=-3+4-4n
3-3n=1-4n
n=-2
B. Correct
C. Incorrect
1=0.75n+3.25
-2.25=0.75n
n=-3
D. Incorrect
-1-22n=-20n-9
8=2n
n=4
The given equations are
(a) Solution by graphing both the equations:
Graph for both the equations (i) and (ii) are in the figure. The point of intersection of both the graph is the solution of the equations.
From the graph, the point of intersection is (4,3)).
Hence, the required solution is (4,3).
(b) Solution by elimination method:
Equations (ii) can be written as -x+y=-1, now multiply it by 2, we have
Add equations (i) and (iii), we have
2x-3y=-1
-2x+2y=-2
__________
Putting the value of y=3 in equation (i), we have
Hence, the required solution is (4,4).
(c) Solution by substitution method:
Substituting the value of y from equation (ii) to equation (i), we have
Putting the value of x=4 in equation (i), we have
.
Hence, the required solution is (4,3).
