Solve the simultaneous equations: 3x + 2y =4 4x + 5y =17
You are trying to find out the value of 'x' and the value of 'y'.
This means that you need to be able to take away one equation from the other.
3x + 2y = 4 - we are going to times this equation by 4
= 12x + 8y = 16
4x + 5y = 17 - we are going to times this equation by 3
= 12x + 15y = 51
Now we are going to take away one equation away from the other:
12x + 15y = 51
- 12x + 8y = 16
This equals 7y = 35
To find out the value of 'y', we then divide 35 by 7.
y = 5
Then to find out the value of 'x', we plug in the y value to one of the equations:
3x + 2(5) = 4
3x + 10 = 4
Take 10 away from 4.
3x = -6
Divide -6 by 3.
x = -2
Therefore, the answer is:
x = -2 and y = 5
EW
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