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Solve the system of equations by substitution. 3/8 x + 1/3 y =17/24 and
x + 7y = 8

User Fabrizio
by
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2 Answers

3 votes

Answer:

1,1

Explanation:

Correct:)

User PQW
by
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\left \{ {{ (3)/(8)x+ (1)/(3)y = (17)/(14) } \atop {x+7y=8}} \right.

To solve this system by substitution, first isolate x in the second equation.


x+7y=8

x+7y-7y=8-7y

x=8-7y

Now, plug this expression (
8-7y) for x in the top equation to solve for y.


(3)/(8) (8-7y)+ (1)/(3) y= (17)/(14)

3- (21)/(8) y+ (1)/(3) y= (17)/(24)

72-63y+8y=17

72-55y=17

-55y=17-72

-55y=-55

y=1

Now that you have y, plug it into the second equation and solve for x.


x+7y=8

x+7(1)=8

x+7=8

x=1

Last step is to plug your x- and y-values in to both equations to check your work.


(3)/(8) (1)+ (1)/(3) y= (17)/(24)


(3)/(8) * (3)/(3) = (9)/(24) ; (1)/(3) * (8)/(8) = (8)/(24)


(9)/(24) + (8)/(24) = (17)/(24) <--True


1+7(1)=8

1+7=8 <--True

Answer:

x=1 \\ y=1
User Travis Reed
by
8.1k points

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