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How to solve for x
7/4x - 3 = 2 + 9/2x​

2 Answers

3 votes

Answer:

X = 11/20

Explanation:

7/4x-3=2+9/2x

We move all terms to the left:

7/4x-3-(2+9/2x)=0

Domain of the equation: 4x!=0

x!=0/4

x!=0

x∈R

Domain of the equation: 2x)!=0

x!=0/1

x!=0

x∈R

We add all the numbers together, and all the variables

7/4x-(9/2x+2)-3=0

We get rid of parentheses

7/4x-9/2x-2-3=0

We calculate fractions

14x/8x^2+(-36x)/8x^2-2-3=0

We add all the numbers together, and all the variables

14x/8x^2+(-36x)/8x^2-5=0

We multiply all the terms by the denominator

14x+(-36x)-5*8x^2=0

Wy multiply elements

-40x^2+14x+(-36x)=0

We get rid of parentheses

-40x^2+14x-36x=0

We add all the numbers together, and all the variables

-40x^2-22x=0

a = -40; b = -22; c = 0;

Δ = b2-4ac

Δ = -222-4·(-40)·0

Δ = 484

The delta value is higher than zero, so the equation has two solutions

We use following formulas to calculate our solutions:

x1=−b−Δ√2ax2=−b+Δ√2a

Δ−−√=484−−−√=22

x1=−b−Δ√2a=−(−22)−222∗−40=0−80=0

x2=−b+Δ√2a=−(−22)+222∗−40=44−80=−11/20

User Blackheart
by
4.3k points
5 votes

Answer:

x = -20/11

Explanation:

and how -(11 x)/4 - 5 = 0

1/4 (7 x - 12) = 1/2 (9 x + 4)

hope this helps

User Leze
by
4.7k points