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5 votes
Solve the simultaneous equations
3x + y = 25
2x – y = 10

1 Answer

6 votes

Answer:

x=7 and y=4

Explanation:

I will use the elimination method:

Since the co-efficient of both y's are the same number but different signs we add the 2 equations to eliminate the y:

3x + y =25
+ + +

2x - y = 10

Simplify:

5x=35

Divide both sides by 5:

5x÷5=35÷5

Simplify:

x=7

Substitute this into either equation 1 or 2 ( I chose 1):

3(7) + y = 25

21 + y = 25

Subtract 21 from both sides and simplify to get y:

21+y-21=25-21

y=4

Therefore x=7 and y=4

User M I P
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