Question

solve 2x-y+3=0, 3x-7y+10=0 by sustitution method

Answer 1

Step-by-step explanation:

We Have :-

$2x - y + 3 = 0 \\ \\ \\ 3x - 7y + 10 = 0$

To Find :-

$x \: and \: y$

Method Used :-

$substitution$

Solution :-

$2x - y + 3 = 0 \\ \\ \\ 2x - y = - 3 \\ \\ \\ - y = - 3 - 2x \\ \\ \\ y = 3 + 2x \: - - - - - (1) \\ \\ \\ putting \: (1) \\ \\ \\ 3x - 7y + 10 = 0 \\ \\ \\ 3x - 7y = - 10 \\ \\ \\ 3x - 7(3 + 2x) = - 10 \\ \\ \\ 3x - 21 - 14x = - 10 \\ \\ \\ - 11x = - 10 + 21 \\ \\ \\ - 11x = 11 \\ \\ \\ x = - 1 \\ \\ \\ putting \: this \: in \: (1) \\ \\ \\ y = 3 + 2x \\ \\ \\ y = 3 + 2( - 1) \\ \\ \\ y = 3 - 2 \\ \\ \\ y = 1$

Answer 2

$\large{\underline{\red{\rm{Given:}}}}$

2x - y + 3 = 0 ----------- eq (1)

3x - 7y + 10 = 0 -------- eq (2)

$\large{\underline{\red{\rm{To\:Find:}}}}$

Value of x and y

$\large{\underline{\red{\rm{Solution:}}}}$

→We are going to solve this by elimination method -

•Multiply eq (1) by 3 and eq (2) by 2

Final equations becomes →

6x - 3y + 9 = 0 and 6x - 14y + 20 = 0

~Solving both the equations -

6x - 03y +09 = 0

6x - 14y + 20 = 0

___________________

$\:(-) \:(+)\:(-)$

___________________

0 + 11y - 11 = 0

___________________

Solving -

11y - 11 = 0

11y = 11

y = $\dfrac{11}{11}$

y = 1

→ Substituting [ y = 1 ] in eq (1)

2x - ( 1 ) + 3 = 0

2x + 2 = 0

2x = - 2

x = $\dfrac{-2}{2}$

x = ( -1 )

→ ${\sf{\red{Value\:of\:x\:=\:( -1 )}}}$

→ ${\sf{\red{Value\:of\:y\:=\:1}}}$