Answer:
This is an inverse variation, and the constant of variation is k = 2.
Step-by-step explanation:
Direct variation is something like:
y = k*x
Where k is the constant of variation.
So as x increases also increases y.
Inverse variation is something like:
y = k/x
k is the constant of variation.
In this case, if x increases, y decreases.
Now let's look at the equation:
-10 + 15*x*y = 20
Let's isolate y in one side of the equation:
15*x*y = 20 + 10 = 30
15*x*y = 30
y = 30/(15*x) = (30/15)/x = 2/x
y = 2/x
Then we can conclude that this is an inverse variation, with a constant of variation equal to 2.
By replacing you get:
5*7-2*11+3*(-1) = 35-22-3= 10
so the answer is 10.
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Answer: since his rock collection has 25 fewer rocks, and his contains 125,
Add that= 125+25=150
Step-by-step explanation: hope this helps
Answer:
You can manipulate both equations into y = mx + b format and end up with the same result of y = 1.2x + 1.4
Step-by-step explanation:
y + 1 = 1.2(x + 2)
y = 1.2x + 2.4 - 1
y = 1.2x + 1.4
y - 5 = 1.2(x - 3)
y = 1.2x - 3.6 + 5
y = 1.2x + 1.4
So essentially, they're the same equation but in different forms.
Answer:
(x-1)(x+5)=0
x=1; x=-5
Step-by-step explanation:
x²+4x=5
x²+4x+2²=5+2²
(x+2)²=3²
(x+2)²-3²=0
(x+2-3)(x+2+3)=0
(x-1)(x+5)=0
(x-1)=0 ; x=1
(x+5)=0; x= - 5
