SOLUTION: prove that if 4x-4=3y+6 and y=2x then x=-5 by substitution y=2x so 4x-4 = 3(2x)+6 4x-4=6x+6 -4x from both sides -4=2x+6 -6 from both sides

Algebra ->  Geometry-proofs -> SOLUTION: prove that if 4x-4=3y+6 and y=2x then x=-5 by substitution y=2x so 4x-4 = 3(2x)+6 4x-4=6x+6 -4x from both sides -4=2x+6 -6 from both sides       Log On


   

Question 221313: prove that if 4x-4=3y+6 and y=2x then x=-5
by substitution y=2x so 4x-4 = 3(2x)+6
4x-4=6x+6
-4x from both sides -4=2x+6
-6 from both sides -10=2x
divide both sides by 2 -5=x
Found 2 solutions by drj, purplerain:
Answer by drj(1380) About Me  (Show Source):
You can put this solution on YOUR website!
prove that if 4x-4=3y+6 and y=2x then x=-5

Step 1. Substitute the values of x and y into the equation to see if it leads to a true statement.

Step 2. Find y when x=-5. Then y=2*(-5)=-10.

Step 3. Substitute x=-5 and y=-10 into 4x-4=3y+6

4*(-5)-4=3(-10)+6

-20-4=-30+6


-24=-24 which is a true statement.

Step 4. ANSWER: x=-5 and y=-10 satisfies both y=-2x and 4x-4=3y+6.

I hope the above steps were helpful.

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Good luck in your studies!

Respectfully,
Dr J



Answer by purplerain(1) About Me  (Show Source):
You can put this solution on YOUR website!
prove that if 4x-4=3y+6 and y=2x then x=-5
by substitution y=2x so, 4x-4 = 3(2x)+6
simplified expression becomes, 4x-4=6x+6
-4x from both sides, 4x-4x-4=6x-4x+6 equals -4=2x+6
-6 from both sides , -10=2x
divide both sides by 2, therefore -5=x or x=-5