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3 years ago

Solve the system of equations and choose the correct answer from the list of options.

Mathematics

2 answers:

earnstyle [38]3 years ago

8 0

X-y=7
y=3x+12
y-3x=12
+
-y+x=7
=
-2x=19
x=-9.5
y=-16.6. Hope it help!

ELEN [110]3 years ago

3 0

Answer: x=-9.5

y=-16.5

Step-by-step explanation:

Hi, to solve this problem we have to apply the substitution method:

x-y =7 (a)

y=3x+12(b)

Replacing the value of "y" in (a) for (b):

x -(3x+12)=7

x-3x-12=7

x-3x =7+12

-2x =19

x=19/-2

x=-9.5

Replacing the value of "x" in (b)

y=3x+12

y=3(-9.5)+12

y= -28.5+12

y=-16.5

Feel free to ask for more if needed or if you did not understand something.

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Sunny_sXe [5.5K]

Answer:

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Step-by-step explanation:

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$B(0,4a-5)=B(0,4(\frac{11}{2})-5)\Rightarrow B(0,17)$

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The area of triangle ABC is

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