Question

if x+y=10 and z+3y=18 then what is x+2y
A. 8
B. 14
C. 16
D.28
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Answer 1

Step-by-step explanation:

x + y = 10

x + 3y = 18

(-) (-) (-)

-------------------

-2y = -8

y = 4

x= 6

x+2y

=6+2×4

=6+8

=14

Answer 2

Answer:

B. 14

Step-by-step explanation:

Given, x + 3y = 18 -------------- eq. 1

x + y = 10 -------------- eq. 2

eq. 1 - eq. 2 --> x + 3y = 18

- x + y = 10

___________

2y = 8

y = 8 ÷ 2 = 4

So, y = 4

Substituting the value of y in eq. 2 gives

----> x + y = 10

x + 4 = 10

x = 10 - 4 = 6

x = 6

Now, x = 6 and y = 4

So, x + 2y = 6 + 2×4 = 6 + 8 = 14

x + 2y = 14

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