2) x = 5
2x + y = 10

3) 5x – 2y =3
y = 2x

Simple, it's plug n chug.
x=5

2(5)+y=10
10+y=10

isolate the variable

10+y=10
-10     -10

y=0

Thus, your x=5 and your y=0.  (0,5)

For the Second equation 

5x-2(2)=3

5x-4=3

then,

5x-4=3
     +4  +4

5x=7

x=1.4

Thus, your x=1.4 and your y=2. (1.4,2)

50% of students voted for candidate b.

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