Question

2) Solve the system of equations using substitution.
2x – 9y = 14
x= -6y +7

Answer 1

(7,0) ---> (x = 7) and (y = 0)

Explanation:

2x – 9y = 14

x= -6y +7 <-- (Substitute for x to above equation)

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2(-6y +7)– 9y = 14

-12y + 14 - 9y = 14 <-- combine like terms

-21y + 14 = 14

-14 = -14 <-- inverse operation on both sides

-21y = 0 <-- Divide

y = 0 <--- Substitute for y to get x ↓

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2x – 9y = 14

2x – 9(0) = 14 <-- Substituted y from above

2x = 14 <-- Divide

x = 7

Answer 2

2(-6y)-9y = 14
-12y - 9y = 14
-21y = 14
y = -2/3