How to solve for the two variables using substitution

Mathematics

1 answer:

kompoz [17]3 years ago

4 0

To subsitute, we need to solve for 1 variable
let's solve for x in bottom equation

x-2y=2
add 2y both sides
x=2y+2
sub 2y+2 for x in other equation

-5(2y+2)+3y=11
-10y-10+3y=11
-7y-10=11
add 10 to both sides
-7y=21
divide both sides by -7
y=-3

sub back
x=2y+2
x=2(-3)+2
x=-6+2
x=-4

(x,y)
(-4,-3)

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Given that:

James is 6 times older than his friend Zach, if Zach added 8 to his age and multiplied this sum by 3 .

To find:

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Solution:

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The sketch of the parabola is attached below

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Find the distance between the focus and the point P using Pythagoras. We have two coordinates; $(2, -0.5)$ and $(x,y)$ .
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Step 2
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