Question

3x-5y=4, 9x-2y=7 substitution method

Answer 1

Answer:

Step-by-step explanation:

3x-5y=4

9x-2y=7

In equation 1

3x-5y=4

So 3x= 4+5y

= x=(4+5y)/3

Now substitute this in equation 2

We get

9 × (4+5y)/3 - 2y = 7

12 + 15y - 2y = 7

13y = 7 - 12

13y = -5

y = -5/13

x = (4+5y)/3

x = (4 -25/13)/3

x = (52-25)/13 (1/3)

x = 27/13 × 1/3

x = 9/13

So x = 9/13 and y = -5/13

Answer 2

Answer:

Step-by-step explanation:

3x-5y=4

9x-2y=7

$3x-5y=4 \\9x-2y=7 \\Deriving an equation from 1st equation \\\\therefore \\\\3x=4+5y ---(1) \\9x-2y=7 ---(2) \\Substituting equation 1 in equation 2 we get \\3(4+5y)-2y=7 \\12+15-2y=7\\12+13y=7\\13y=7-12 \\13y=-5\\y= -5/13 \\ \\Putting the value of y in equation (1) \\3x=4+5-5/13 \\thererfore the value of x=9/13$