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2. What is the solution to the equation
1/2x + 3/2(x+1) - 1/4=5?

User Shulem
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2 Answers

5 votes

1/2x+3/2(x+1)-1/4=5 (Expand the polynomial)

(1/2x+3/2x)+3/2-(1/4)=5

4/2x+3/2-(1/4)=5

4/2x+(3/2–1/4)-(3/2–1/4)=5-(3/2–1/4)

4/2x+0=5-(3/2–1/4) (Express the fractions on the right side of the equation in the common denominator 4)

2x=5-(6/4–1/4)

2x=5-(5/4)

2x=3 3/4

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

x=15/4(1/2)

x=

15/8 or 1 7/8 as a mixed fraction or 1.875 as a decimal numeral

PROOF

If x=15/8, then the inverse of the equation 1/2x+3/2(x+1)-1/4=5 returns

2x+(6/4–1/4)=5

2(15/8)+(6/4–1/4)=5

15/4+(5/4)=5

(15+5)/4=5

20/4=5 and

5=5 proves the root (zero) x=15/8 of the statement 1/2x+3/2(x+1)-1/4=5

C.H.

1/2x+3/2(x+1) --1/4=5

1/2 (1/x+3/ (x+1) =5+1/4

1/x + 3/x+1 =(5+1/4) ×2/1

x+ 1 +3x /x (x+1) = 10+1/2 =21/2

4x+1 = 21/2 [x^2+x]

8x+2= 21x^2+21x

21x^2 +-13 x -2 =0

a =21 b= 13 c= -2

X= [13 + -- (169 -- 4×21× -2)^1/2 ] /2×21

=[13 + - ( 169 + 168 )^1/2] /2×21

Discriminat =169+168=337 >0

User Fernando Vellozo
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4.9k points
0 votes

The answer to this question is

x=15/8

1/2x+3/2(x+1)-1/4=5

1/2x+3/2(x+1)-1/4=5

(1/2x+3/2x)+3/2-(1/4)=5

4/2x+3/2-(1/4)=5

4/2x+(3/2–1/4)-(3/2–1/4)=5-(3/2–1/4)

4/2x+0=5-(3/2–1/4)

2x=5-(6/4–1/4)

2x=5-(5/4)

2x=3 3/4

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

x=15/4(1/2)

x=15/8

User Covariance
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4.7k points