If you would like to solve the system of equations x + y = 3 and 2x - y = 6, you can do this using the following steps:
<span>x + y = 3 ... y = 3 - x
2x - y = 6
</span>_________
<span>2x - y = 6
</span>2x - (3 - x) = 6
2x - 3 + x = 6
3x = 6 + 3
3x = 9 /3
x = 9/3
x = 3
<span>y = 3 - x = 3 - 3 = 0
</span>
The correct result would be x = 3.
4 + 2x = 12
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Take away 4 from both sides:
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2x = 8
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Divide by 2 on both sides:
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x = 4
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Answer: x = 4
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The number is x
it is negative
the square is 28 more than 3 times itself
x²=28+3x
minus (28+3x)
x²-3x-28=0
factor
(x-7)(x+4)=0
set to zero
x-7=0
x=7
this is not the answer because we were told the number was negative
x+4=0
x=-4
correct
the number is -4
test
(-4)²=28+3(-4)
16=28-12
16=16
check
the number is -4
Ok so you can see 2 triangles that i highlighted, flip it so it is the same direction as you can see from the drawing
using the similar triangle equation
you get
136/64 = x/136
cross multiply and get
64x=18496
x=289
hope it help
