Question

How do you solve 3x - 4y = -30 and 7x + 4y = 10?

Answer 1

Solution:

Given system of equations:

3x-4y=-30----(1)

7x+4y=10-----(2)

Add equations (1)&(2),we get

10x=-20

=> x = (-20)/10

=> x = -2

Now ,

substitute x=-2 in equation (2),

we get

7(-2)+4y = 10

=> -14+4y=10

=> 4y = 10+14

=> 4y = 24

=> y = 24/4

=> y = 6

Therefore,

x = -2

y = 6

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