1/3x + 1/4y = 7
1/3x - 3/4y = -9
Make one of the equations negative to eliminate the x's.
-(1/3x + 1/4y) = -(7)
-1/3x - 1/4y = -7
1/3x - 3/4y = -9
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-y = -16
y = 16
Now solve for x. Use either equation.
1/3x + 1/4(16) = 7
1/3x + 4 = 7
Eliminate the fraction by multiplying the equation by three.
3(1/3x + 4) = 3(7)
x + 12 = 21
x = 21 - 12
x = 9
Solution:
(9, 16)
Solve the following system of equations by the elimination method.
1/3x+1/4y=7
1/3x-3/4y=-9
a)The solution is___?(Type an ordered pair. Use integers or fractions for any numbers in the expression)
b)Infinitely many solutions
c)No solution
2 answers
thank you