Answer:
2.0
Step-by-step explanation:
x = age
y = average systolic blood pressure
x₁ = 40 years old, y₁ = 110 systolic blood pressure
x₂ = 50 years old, y₂ = 130 systolic blood pressure
∴ Slope of the regression line is 2.0
Here i how I would do it:<span>f(x)=−<span>x2</span>+8x+15</span>
set f(x) = 0 to find the points at which the graph crosses the x-axis. So<span>−<span>x2</span>+8x+15=0</span>
multiply through by -1<span><span>x2</span>−8x−15=0</span>
<span>(x−4<span>)2</span>−31=0</span>
<span>x=4±<span>31<span>−−</span>√</span></span>
So these are the points at which the graph crosses the x-axis. To find the point where it crosses the y-axis, set x=0 in your original equation to get 15. Now because of the negative on the x^2, your graph will be an upside down parabola, going through<span>(0,15),(4−<span>31<span>−−</span>√</span>,0)and(4+<span>31<span>−−</span>√</span>,0)</span>
To find the coordinates of the maximum (it is maximum) of the graph, you take a look at the completed square method above. Since we multiplied through by -1, we need to multiply through by it again to get:<span>f(x)=31−(x−4<span>)2</span></span><span>
Now this is maximal when x=4, because x=4 causes -(x-4)^2 to vanish. So the coordinates of the maximum are (4,y). To find the y, simply substitute x=4 into the equation f(x) to give y = 31. So it agrees with the mighty Satellite: (4,31) is the vertex.</span>
It's another word for unit rate if that helps
Let n be a number of balls: n = 14
In one pan you have 8 balls: 8n
In the other pan you have the rest of balls (14 - 8 = 6) along with a <span>weight of 20 grams = 6n + 20
So the pans are balanced:
8n = 6n + 20
Now, just solve the equation:
8n - 6n = 20
2n = 20
n = 20/2
n = 10
So, you know that a ball weights 10 grams.</span>
Answer:
Zero
Step-by-step explanation:
3x - 7 = 3x - 9 + 2
3x - 7 = 3x - 7
Add 7 on both sides
3x = 3x
Subtract 3x you get 0.
Hope this helps.
