Question

3x + 4y =10 and 2x + 10y = 20 solve this by substitution method

Answer 1

Answer:

$3x + 4y = 10$

$x = \frac{10 - 4y}{3}$

Now putting X's value in another equation.

$2( \frac{10 - 4y}{3} ) + 10y = 20$

$\frac{20 - 8y + 30y}{3} = 20$

$20 + 22y = 60$

$22y = 40$

$y = \frac{40}{22} = \frac{20}{11}$

Put Y's value in above equation to get X

$x = \frac{10 - 4 (\frac{20}{11}) }{ 3}$

$x = \frac{10 - \frac{80}{11} }{3}$

$x = \frac{30}{3} = 10$

$∴x = 10 \: \: y = \frac{20}{11}$

Hope it helps you..!!!!

Answer 2

Step-by-step explanation:

3x+4y=10

x = \frac{10 - 4y}{3}x=

3

10−4y

Now putting X's value in another equation.

2( \frac{10 - 4y}{3} ) + 10y = 202(

3

10−4y

)+10y=20

\frac{20 - 8y + 30y}{3} = 20

3

20−8y+30y

=20

20 + 22y = 6020+22y=60

22y = 4022y=40

y = \frac{40}{22} = \frac{20}{11}y=

22

40

=

11

20

Put Y's value in above equation to get X

x = \frac{10 - 4 (\frac{20}{11}) }{ 3}x=

3

10−4(

11

20

)

x = \frac{10 - \frac{80}{11} }{3}x=

3

10−

11

80

x = \frac{30}{3} = 10x=

3

30

=10

∴x = 10 \: \: y = \frac{20}{11}∴x=10y=

11

20