Question

Solve the system of equations below.
(x+y=21
2x = 33+ y

Answer 1

Answer:

(18, 3 )

Step-by-step explanation:

Given the 2 equations

x + y = 21 → (1)

2x = 33 + y → (2)

Rearrange (2) expressing y in terms of x by subtracting 33 from both sides

y = 2x - 33 → (3)

Substitute y = 2x - 33 into (1)

x + 2x - 33 = 21, that is

3x - 33 = 21 ( add 33 to both sides )

3x = 54 ( divide both sides by 3 )

x = 18

Substitute x = 18 into (3) for corresponding value of y

y = (2 × 18) - 33 = 36 - 33 = 3

Solution is (18, 3 )

Answer 2

Answer:

Step-by-step explanation:

x+y = 21 —> (A)

2x = 33 + y — (B)

Form eq B

2x = 33 + y

Or y = 2x - 33

By putting the value of y in equation A

x + 2x -33 = 21

3x = 21 + 33

3x = 54

x = 54/3

x = 18

Now,

y = 2 (18) -33

= 36 - 33

= 3

Thus, s.s ={( 18,3)}