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3 years ago

Y=4x and 3x+y=-21. Substitute

Mathematics

1 answer:

gizmo_the_mogwai [7]3 years ago

5 0

value of x= -3 and value of y = -12

Solution set is (-3,-12)

Step-by-step explanation:

We need to solve the system of equations using substitution

The system of equations are:

$y=4x\\3x+y=-21$

Solving:

Let

$y=4x\,\,eq(1)\\3x+y=-21\,\,eq(2)$

Solving:

Putting value of y from equation 1 into equation 2

$3x+y=-21\\3x+4x=-21\\7x=-21\\x=-21/7\\x=-3$

So, value of x = -3

Now, putting value of x into equation 1 and find value of y

$y=4x\\y=4(-3)\\y=-12$

Value of y = -12

So, value of x= -3 and value of y = -12

Solution set is (-3,-12)

Keywords: System of equations

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Answer:

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Step-by-step explanation:

First we have to find the equation of line which passes through (6,3) and (8,4).

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So, using the point in the line, that is using x=n , y=-2

we get

n-2(-2)=0

or, n+4=0

or, n=-4

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