How do you do this Problem? 1/4x + 3/2x = 7?

I can not figure this out! Someone please help!!!!!!

Comments

  • (1/4 + 6/4) x = 7 : add fractions using common denom (multply 2nd fraction by 2).

    7/4 x = 7 : added

    7 x = 28 : multiply by 4

    x = 4 : divide by 7

    If the problem is actually 1 / (4x) + 3 / (2x) = 7 , the working is similar, but the answer is quite different than the above.

    1 / (4x) + 6 / (4x) = 7 : common denom by mult 2nd by 2

    7 / (4x) = 7 : add

    {7 / (4x)} (4x) = 7 (4x) ; take both sides by 4x to get it out of the denominator

    7 = 28x : multiply and simplify

    x = 1/4 : divide by 28

  • Ok well first you need a common denominator so that you can combine your x's. So1/4 x + 3/2 x is the same as 1/4x + 6/4x which is 7/4x. Then you multiply both sides by 4/7. That leaves x by itself on one side and 7 times 4/7 is equal to 4.

    So your answer is x=4

  • 1/4x + 3/2x = 7

    Multiply both sides by x:

    x(1/4x + 3/2x) = 7x

    x/4x + 3x/2x = 7x

    The x/x cancel:

    1/4 + 3/2 = 7x

    Put everything over common denominator (4)

    1/4 + 6/4 = 28x/4

    ( 6/4 = 3/2 and 28/4 = 7)

    Multiply both sides by 4

    4(1/4 + 6/4) = 4(28x/4)

    The 4/4 cancel:

    1 + 6 = 28x

    7 = 28 x

    divide both sides by 28

    7/28 = 28x/28 = x

    x = 7/28 = 1/4

  • 1/4x + 3/2x = 7

    x + 6x = 28

    7x = 28

    x = 4

    1/4*4 + 3/2*4 = 1 + 6 = 7 QED

  • I'll assume this is (1/4)x+(3/2)x = 7

    You need to get a common denominator. In this case just multiply the right term by 2/2:

    (1/4)x+(6/4)x = 7

    Add like terms:

    (7/4)x = 7

    Divide both sides by 7/4:

    x = 4

  • 1/4x +3/2x = 7

    1/4x 6/4x = 7

    7/4x = 7

    x = 7 / (7/4)

    x = 7 * 4/7

    x = 28/7

    x = 4

    Proof:

    1/4(4) + 3/2(4) = 7

    1 + 6 = 7

  • 1/(4x) + 3/(2x) = 7

    Multiply both sides by 4x

    4x/4x + (3)(2)(2x)/2x = (7)(4x)

    1 + 6 = 28x

    28x = 7

    x = 1/4

    OR==========

    (1/4)x + (3/2)x = 7

    Multiply both sides by 4

    x + 6x = 28

    7x=28

    x=4

  • u must first get common denominators by mult. 3/2x by two...

    so it would look like this... 1/4x + 6/4x= 7...then u add the two terms so it looks like this... 7/4x=7

    Then u mult. both sides by 4/7 to get the x by itself

    so you answer is 1/4

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