Solve the following simultaneous equations : with the help of steps1. x + 2y = 1, 3x - y = 17

Mathematics

1 answer:

IRISSAK [1]3 years ago

6 0

Answer:

x = 5, y = -2

Step-by-step explanation:

Given equations:

x + 2y = 1
3x - y = 17

From the first equation we get:

x = 1 -2y

Substitute x in the second equation, find y:

3x - y = 17
3*(1-2y) - y = 17
3 - 6y - y = 17
-7y = 17 - 3
-7y = 14
y = -14/7
y = -2

Find x:

x = 1 - 2y
x = 1 - 2*(-2)
x = 1 + 4
x = 5

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