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If a + 2b + 3c = 0 " then " a/3+(2b)/3+c...

If `a + 2b + 3c = 0 " then " a/3+(2b)/3+c=0` and comparing with line ax + by + c, we get `x = 1/3 & y = 2/ 3` so there will be a point `(1/3,2/3)` from where each of the lines of the form ax + by + c = 0 will pass for the given relation between a,b,c . We can say if there exists a linear relation between a,b,c then the family of straight lines of the form of `ax + by +c ` pass through a fixed point .
If a , b, c are consecutive odd integers then the line ax + by + c = 0 will pass through

A

(2,-1)

B

(2,1)

C

(-1,2)

D

(1,-2)

Text Solution

AI Generated Solution

The correct Answer is:
To solve the problem step by step, we need to analyze the given equation and the conditions provided. ### Step 1: Understand the given equation We start with the equation: \[ a + 2b + 3c = 0 \] ### Step 2: Rewrite the equation We can rewrite this equation in terms of \( c \): \[ 3c = - (a + 2b) \] \[ c = -\frac{1}{3}(a + 2b) \] ### Step 3: Substitute into the line equation We need to compare this with the line equation of the form: \[ ax + by + c = 0 \] Substituting \( c \) into the line equation gives: \[ ax + by - \frac{1}{3}(a + 2b) = 0 \] ### Step 4: Rearranging the equation Multiplying through by 3 to eliminate the fraction: \[ 3ax + 3by - (a + 2b) = 0 \] This simplifies to: \[ 3ax + 3by - a - 2b = 0 \] ### Step 5: Grouping terms Rearranging gives: \[ a(3x - 1) + b(3y - 2) = 0 \] ### Step 6: Analyzing the coefficients For this equation to hold for all values of \( a \) and \( b \), we must have: \[ 3x - 1 = 0 \quad \text{and} \quad 3y - 2 = 0 \] ### Step 7: Solving for \( x \) and \( y \) From \( 3x - 1 = 0 \): \[ 3x = 1 \] \[ x = \frac{1}{3} \] From \( 3y - 2 = 0 \): \[ 3y = 2 \] \[ y = \frac{2}{3} \] ### Step 8: Conclusion about the point Thus, we find that the point through which all lines of the form \( ax + by + c = 0 \) pass is: \[ \left( \frac{1}{3}, \frac{2}{3} \right) \] ### Step 9: Considering consecutive odd integers If \( a, b, c \) are consecutive odd integers, we can represent them as: - Let \( a = n \) (first odd integer) - Let \( b = n + 2 \) (second odd integer) - Let \( c = n + 4 \) (third odd integer) ### Step 10: Substitute into the line equation Substituting these into the line equation \( ax + by + c = 0 \): \[ n x + (n + 2) y + (n + 4) = 0 \] ### Step 11: Rearranging This can be rearranged to: \[ n(x + 1) + 2y + 4 = 0 \] ### Step 12: Finding fixed point To find the fixed point, we can set \( n = 0 \) (which is valid since we are looking for a point independent of \( n \)): \[ 2y + 4 = 0 \] \[ y = -2 \] Thus, the line will pass through the point: \[ (1, -2) \] ### Final Answer The line \( ax + by + c = 0 \) will pass through the point: \[ (1, -2) \] ---
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Knowledge Check

  • If a + 2b + 3c = 0 " then " a/3+(2b)/3+c=0 and comparing with line ax + by + c, we get x = 1/3 & y = 2/ 3 so there will be a point (1/3,2/3) from where each of the lines of the form ax + by + c = 0 will pass for the given relation between a,b,c . We can say if there exists a linear relation between a,b,c then the family of straight lines of the form of ax + by +c pass through a fixed point . If a , b,c are in A.P., then the line ax + 2by + c = 0 passes through

    A
    (0,0)
    B
    (1,-2)
    C
    (-1,1)
    D
    (1,-1)
  • If a + 2b + 3c = 0 " then " a/3+(2b)/3+c=0 and comparing with line ax + by + c, we get x = 1/3 & y = 2/ 3 so there will be a point (1/3,2/3) from where each of the lines of the form ax + by + c = 0 will pass for the given relation between a,b,c . We can say if there exists a linear relation between a,b,c then the family of straight lines of the form of ax + by +c pass through a fixed point . If a , b, c are in H.P . then the line acx + bcy + ab = 0 passes through,

    A
    (1,-2)
    B
    (1,2)
    C
    (-2,1)
    D
    (2,-1)
  • If a+b+c=0 then the line 3ax+by+2c=0 passes through the fixed point

    A
    `(2,(2)/(3))`
    B
    `((2)/(3),2)`
    C
    `(2,(2)/(3))`
    D
    `((2)/(3),(2)/(3))`
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