X plus 7y equals 39 and 3x minus 2y equals 2?

Answer 1

x + 7y = 39 ....... Eq.1

3x - 2y = 2 ....... Eq.2

multiply Eq.1 with (-3) and so Eq.1 will be :

-3x - 21y = -117

3x - 2y = 2

_________________ by Elimination method ( Eq.1 + Eq.2 ) the result will we :

- 21y - 2y = - 115

-23y = -115

Y = 5

to find the value of x, put the value of y in Eq.1 :

x + 7y = 39

x = 39 - 7y

x = 39 - 7(5)

X = 4

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you can solve it in another way by using substitution method:

x + 7y = 39 ....... Eq.1 ,, you can write it in another form, x = 39 - 7y

3x - 2y = 2 ....... Eq.2

Put the value of Eq.1 on Eq.2

3(39 - 7y) - 2y = 2

117 - 21y - 2y = 2

117 - 23y = 2

23y = 115 ............ Y = 5

to find the value of X , put the value of Y in Eq.1

x = 39 - 7y

x = 39 - 7(5)

x = 39 - 35 .............. X = 4

and so in both ways....you got the same answer choose the easiest way for you :)

good luck my friend...