Question

Solve using substitution method

2x+3y=23
4x+y=21

Answer 1

Answer:

x = 4 & y = 5

Step-by-step explanation:

(2x + 3y = 23) × 2

(4x + y = 21) × 1

This done to equalize the equations

4x + 6y = 46 - ( i )

4x + y = 21 - ( ii )

On subtracting equation ( ii ) from equation ( i )

4x + 6y = 46

4x + y = 21

- - -

-------------------

0 + 5y = 25

5y = 25

y = 25/5

y = 5

Equating y = 5 in equation ( ii )

4x + y = 21

4x + 5 = 21

4x = 21 - 5

4x = 16

x = 16÷4

x = 4

You can check the answer by putting the values in the other equation as well

2x + 3y = 23

2*4 + 3*5 = 8+ 15 = 23