11-03-2020
Mathematics

contestada

What is the value of x and y if 21x+7y=42 and -5x+5y=10 are equal

Respuesta :

dannielle dannielle

11-03-2020

Answer:

-5x/5 +5y/5=10/5=2

y-x=2

y=x+2

21x+7*(x+2)=42

21x+7x+14=42

28x=42-14

28x=28

x=1

y=1+2

y=3

Step-by-step explanation:

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