Question

answer please step by step by simultaneous equation​

Answer 1

*3 gives. 12x + 21y =63

3x+ 21y =80(-)

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9x= -17

Answer 2

Step-by-step explanation:

question 1) 7y = 21 - 4x ( X = 2 )

7y = 21 - 4*2

7y = 21 - 8

7y = 13

y = 13/7

question 2) 21y = 80 - 3x ( X = 5 )

21y = 80 - 3*5

21y = 80 - 15

21y = 65

y = 65/21