Question

simultaneous equations 2x + y = 21 x - y = 6

Answer 1

Step-by-step explanation:

this is substitution method

Answer 2

Answer:

2x + y = 21

+

x - y = 6

_________

3x = 27

x = 27 ÷ 3

x= 9

x - y = 6

9 - y = 6

9 - 6 = y

3 = y

Therefore, x= 9 and y = 3