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HELP PLZ
Solve each proportion for the variable​

HELP PLZ Solve each proportion for the variable​-example-1

2 Answers

3 votes

Answer:

Explanation:

Key skills: Proportions, One variable equations, Multiplication, Distribution Property

1) The best approach to this problem is with cross multiplication.

Cross multiplication is where we multiply the numerator of one fraction with the denominator of the other fraction, and the denominator of one fraction with the numerator of the other fraction.

2) Here we would do: 4(2x+5) and 12(x+2)

3) Since this is a proportion --> 4(2x+5) = 12(x+2)

4) Now, we use distribution property to expand both.

4(2x+5) --> 8x+ 20 12(x+2) --> 12x+24

5) With simplifying we can solve for x:

  • 8x+20=12x+24
  • We then move the 12x to the left side, and the 20 to the right side: 8x-12x=24-20
  • Now we combine like terms: -4x=4
  • Then we divide by -4 on both sides to solve for x. x=-1

If you plug in x=-1 back into the equation: 4/12= 1/3

4/12 does equal 1/3 so x= -1 is the right answer.

Hope you have a nice day and understood this problem explanation!! :D

User TEEKAY
by
3.6k points
7 votes

Answer:

x = -1

Explanation:

4/12 can be simplified to 1/3

1 x+2

--- = --------------

3 2x+5

Using cross products

1 ( 2x+5) = 3 (x+2)

Distribute

2x+5 = 3x+6

Subtract 2x from each side

2x+5-2x = 3x+6-2x

5 = x+6

Subtract 6 from each side

5-6 = x+6-6

-1 =x

User Matt Roberts
by
3.5k points