There is a special kind of substitution which some books call it by comparison.
When the two equations are both
y=some function of x
y=some other function of x, then
we can substitute the second equation into the first giving
some function of x = some other function of x and start solving.
For example,
<span>y = –2x + 8
y = x – 1
substitute second into first
x-1=-2x+8
isolate x on left,
3x=9
x=3
second step is to substitute x=3 into second equation to get
y=x-1=3-1=2
Therefore the solution is (3,2)</span>
X - 4 > 3
x - 4 + 4 > 3 + 4
x > 7
solution: x must be greater than 7
Hello from MrBillDoesMath!
Answer:
See Discussion below
Discussion:
A function f is even if f(-x) = f(x)
f(x) f(-x) Are they equal?
----------------------------------------------------------------------------------------
-x^8 + 2x^6-5x -(-x)^8 + 2(-x)^6 + 5x No
3 abs(x) - 4 3 abs(-x) -4 Yes
log5 x^2 log5 (-x)^2 Yes
(6x)^ (1/7) (-6x)^(1/7) No
e^(x^2-x) e^( (-x)^2+x) No
(x^8 +5x^2)^(-1) ( (-x)^8 + 5 (-x)^2) ^(-1) Yes
Answers with Yes, above are even functions.
Regards,
MrB
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