Solve these pair of simultaneous questions: 3x+2y=17 4x-y=30
Let's solve for x first by substituting y in terms of x.
4x-y=30
y=4x-30
3x+2y=3x+2(4x-30)=3x+8x-60=11x-60
11x-60=17
11x=77
x=7
Now let's solve for y by substituting x for 7
3x +2y=17
3(7)+2y=17
21+2y=17
2y=17-21
2y=-4
y=-2
We can check if our answers are correct by substituting them in the equations
3x+2y=17
3(7)+2(-2)=21-4=17
4x-y=30
4(7)-(-2)=28+2=30
JY
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