Question 387180: Please help me solve this equation:
If 2x + 2y = 10 and y = x + 1, what is the value of x?
Thanks!
Found 2 solutions by stanbon, gwendolyn:
Answer by stanbon(75887)   (Show Source):
You can put this solution on YOUR website! If 2x + 2y = 10
ans y = x + 1,
what is the value of x?
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Divide thru the 1st eq. by 2 to get:
x + y = 5
x - y = -1
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Add and solve for "x"
2x = 4
x = 2
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Since x+y = 5
2+y = 5
y = 3
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Solution: (2,3)
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Cheers,
Stan H.
Answer by gwendolyn(128)  (Show Source):
You can put this solution on YOUR website! First, we can substitute the value of y into the first equation.
2x+2y=10
2x+2(x+1)=10
Then, we distribute the two in the equation's first half.
2x+2(x+1)=10
2x+2x+2=10
Then, we combine the two "2x"s
4x+2=10
Next, we subtract 2 from both sides.
4x+2=10
4x+2-2=10-2
4x=8
Finally, we divide both sides by four to isolate the variable.
4x=8
x=2
To check:
y=x+1
y=4+1
y=5
2x+2y=10
 =10
4+6=10
10=10
This is correct, so x is equal to 2.
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