Assuming that the second equation is supposed to be y + (2/3)x = b. If it is as written in the problem, it doesn't show what it equals and there's no way to determine b.
Substitute 3 for x.

-4(3)+2y=8

-12 + 2y = 8

Add 12 to both sides.

2y = 20

Divide both sides by 2.

y=10

So the point is (3,10)

Plug that point into the second equation to find b.

10 + (2/3)3 = b = 10+2 =12

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Answer by mananth(16946)   (Show Source): You can put this solution on YOUR website!
-4x+2y=8 crosses another line with the equation y+(2/3)x+b at the point (3,a)
plug (3,a) for the line
-4x+2y=8
-4(3)+2a=8
-12+2a=8
2a=20
a=10
y=(2/3)x+b
(3,10) is the point
10=(2/3)*3+b
10=2+b
b=8
m.ananth@hotmail.ca
Answer by stanbon(75887)   (Show Source): You can put this solution on YOUR website!
If the line defined by the equation -4x+2y=8 crosses another line with the equation y=(2/3)x+b at the point (3,a), what is the value of b?
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If (3,a) satisfies both equations you get:
-12+2a = 8
a = 2 + b
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Substitute for "a" and solve for "b":
-12 + 2(2+b) = 8
2+b = 10
b = 8
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Cheers,
Stan H.
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