Question

find x and y by substituting method (class10) 2x-7y=10 ,3x+2y=10

Answer 1

2x - 7y = 10
2x = 10 + 7y
x = (10 + 7y)/2

Substituting this value of x in the equation of 3x + 2y = 10

3[{10 + 7y)/2] + 2y = 10

(30 + 21y)/2 + 2y = 10

(30 + 21y + 4y)/2 = 10

30 + 25y = 20

25y = - 10

y = - 10/25 = - 2/5

3x + 2(-2/5) = 10

3x - 4/5 = 10

(15x - 4)/5 = 10

15x - 4 = 50

15x = 54

x = 54/15

x = 18/5

x = 18/5 and y = -2/5

Answer 2

hi buddy

well iam not 10th
iam 7th

but here your answer goes like this

let

2x-7y=10 ---------->1

3x+2y=10 ----------->2
frm equation 1
make x as subject

=> 2x-7y=10

= 2x=10+7y

= x = (10+7y) /2

now substitute x in equation 2

=> 3 × (10 + 7y)/2 + 2y = 10

=> ( 30 + 21y) / 2 + 2y = 10

=>( 30 + 21y + 4y ) / 2 = 10

=> 30 + 25y = 20

=> 25y = (-10)

=> y = (-10)/25

=> y = (-0.4)


now substitute y in eq 2

you will get

3x + 2×(-0.4) = 10

3x + (-0.8) = 10

3x = 10+0.8

3x = 10.8

x = (10.8) /3

x = 3.6


there fore,

x=3.6

y = (-0.4)


i hope it helped you



thanks !!!!