Question

solve the following paris of equations by substitution methos 7x-15y=2 and x+2y=3​

Answer 1

Answer:

value of x is 49/29 and y is 19/29

Step-by-step explanation:

give that

7x-15y=2--->equation-1

x+2y=3----->equation-2

consider equation-2

=>x+2y=3

=>x=3-2y

substitute the value of x in equation-1

=>7(3-2y)-15y=2

=>21-14y-15y=2

=>21-29y=2

=>29y=19

=>y=19/29

put value of y in x=3-2y

=>x=3-2(19/29)

=>x=(87-38)/29

=>x=49/29

Answer 2

Answer:

$7x - 15y = 2 \\ \: \implies7x = 2 + 15y \\ \implies \: x = \frac{2 + 15y}{7} \: \: \: \: \: \rightarrow(i) \\ \\ x + 2y = 3 \\ \implies\frac{2 + 15y}{7} + 2y = 3 \: (putting \: x = \frac{2 + 15y}{7} ) \\ \implies \frac{2 + 15y + 14y}{7} = 3 \\ \implies15y + 14y = 3 \times 7 - 2 \\ \implies29y = 21 - 2 \\ \implies \: y = \frac{19}{29} \\ \\ \\ \: \: substituting \: the \: value \: of \: y \: in \: equation \: (i) \\ 7x - 15 \times \frac{19}{29} = 2 \\ \implies7x - \frac{285}{29} = 2 \\ \implies7x = 2 + \frac{285}{29} \\ \implies7x = \frac{58 + 285}{29} \\ \\ \: \implies7x = \frac{343}{29 } \\ \\ \implies \: x = \frac{343}{203} \\ \\ \implies \: x = \frac{49}{29} \\ \\ \therefore \: x = \frac{49}{29} \\ \\ y = \frac{19}{29}$