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3 years ago

Please help im desperate no. 48 and 49

Mathematics

2 answers:

stealth61 [152]3 years ago

8 0

Answer:

C and (3, 6 )

Step-by-step explanation:

(48)

Since given y = 2x the best method of solving is by substitution C

(49)

Given the 2 equations

3x + y = 15 → (1)

y = 2x → (2)

Substitute y = 2x into (1)

3x + 2x = 15

5x = 15 ( divide both sides by 5 )

x = 3

Substitute x = 3 into (2) and evaluate for y

y = 2x = 2 × 3 = 6

solution is (3, 6 )

exis [7]3 years ago

3 0

Answer:

48. option C : Substitution

49. Option D : ( 3, 6)

Step-by-step explanation:

3x + y = 15 ------------- ( 1 )

y = 2x ------------------- ( 2 )

Substitute ( 2 ) in ( 1 ) :

3x + y = 15

3x + 2x = 15

5x = 15

$x = \frac{15}{5} = 3$

Substitute x in ( 2 ) :

y = 2x

y = 2 × 3 = 6

The solution to the system of equation is ( 3 , 6 )

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alina1380 [7]

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Ilya [14]

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3 years ago

Please help im desperate no. 48 and 49​

Please help im desperate no. 48 and 49