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Solve the system of equations by substitution.

3x+y = 10
7x+ 2y= 24

A. (2,4)
B. (2,-6)
C. (4,-2)
D. (2,-4)

If you can, explain step by step please :)

User MLowijs
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1 Answer

2 votes

Answer:

C

Explanation:

3x+y=10---(1)

7x+2y=24---(2)

From(1)

3x+y=10

y=10-3x---(3)

Substitute(3)into(2)

7x+2y=24

7x+2(10-3x)=24

7x+20-6x=24

x+20=24

x=24-20

x=4

Substitute x=4 into (1)

3x+y=10

3(4)+y=10

12+y=10

y=10-12

y=-2

User Tony Noriega
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