Question

for the pair of linear equation 4x + 5y =24, 5x + 4y= 21​

Answer 1

Answer:

20 x + 25y = 120 eq 3

20x + 16y = 84 eq 4

subtract eq 3 and eq 4

9y = 36

y= 4

putting y in eq 1

4x + 5×4 =24

4x = 24 - 20

4x = 4

x = 1

Answer 2

Answer:

4x+5y=24,5x+4y=21

Step-by-step explanation:

4x+5y=24

4x=24-5y

x=24-5y/4

x=24-5*4/4

x=24-20/4

x=4/4

x=1

5x+4y=21

5(24-5y/4)+4y=21

120-25y/4 +4y=21

120-25y+16y/4=21

120-9y=84

-9y=84-120

-9y=-36

y=-36/-9

y=4

Hence, the value of x=1 and y=4