Find the values of x and y. 18. 120°=(2x + y)° (2x - y)°=140°

Mathematics

1 answer:

sleet_krkn [62]3 years ago

8 0

Answer:

x = 65, y = - 10

Step-by-step explanation:

Given the 2 equations

2x + y = 120 → (1)

2x - y = 140 → (2)

Adding the 2 equations term by term will eliminate y, that is

4x = 260 ( divide both sides by 4 )

x = 65

Substitute x = 65 into either of the 2 equations and evaluate for y

Substituting into (1)

2(65) + y = 120

130 + y = 120 ( subtract 130 from both sides )

y = - 10

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