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{4y+2x =4, 3y -3x = -6} solve by substatution and check answer

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2 Answers

(1)     4y + 2x = 4
(2)     3y - 3x = -6
 
Let's solve equation (1) for x:
4y + 2x = 4
2x = 4 - 4y
 
x = 2 - 2y
 
Now let's substitute 2-2y in place of x in equation 2:
3y - 3x = -6                     [Equation (2)]
3y - 3(2-2y) = -6              [Substituted 2-2y for x]
3y - 6 + 6y = -6
9y = 0
 
y = 0
 
Find x:
x = 2 - 2y
x = 2 - 2(0)
x=2
 
Check:
4y+2x = 4
4(0)+2(2) = 4
4 = 4
 
3y-3x=-6
3(0)-3(2) = -6
-6 = -6
 
Hi Adena,
 
4y+2x=4......eq 1
3y-3x=-6.......eq 2
 
Divide eq 2 by 3, we get,
 y-x=-2
adding x on both the sides,
y=x-2..........eq 3
 
substituting value of y in eq 1, we get,
4(x-2)+2x=4
4x-8+2x=4
6x=12
x=2
substituting value of x in  eq 3, we get,
y=2-2
y=0
 
Check: LHS of eq 1=4y+2x=4(0)+2(2)= 4=RHS
           
           LHS of eq 2= 3y-3x=3*0-3*2=-6 = RHS
 
Ans: { x=2,y=0}
 
 
Meena from Strongsville,OH