please help im desperate no. 48 and 49
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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
[tex]x = \frac{15}{5} = 3[/tex]
Substitute x in ( 2 ) :
y = 2x
y = 2 × 3 = 6
The solution to the system of equation is ( 3 , 6 )
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 )