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>
Answer:
y = -3x - 16
Step-by-step explanation:
Point-slope form: y - y1 = m(x - x1)
Given: y - 2 = -3(x + 6)
Slope-intercept form: y = mx + b
To write the equation in slope-intercept form, we need to know the slope(m) and the y-intercept(b). By looking at the given equation, we can see that the slope is -3. We are also given the value of one point: (-6, 2).
To find the y-intercept, input the given values of the slope and the point into the equation format and solve for b:
y = mx + b
2 = -3(-6) + b
2 = 18 + b
Subtract 18 from both sides of the equation to isolate b:
2 - 18 = 18 - 18 + b
-16 = b
The y-intercept is -16.
Now that we know the slope and the y-intercept, we can write the equation:
y = -3x - 16
$75.14. formula as follows ($79.99 - (($79.99/100)x12)) + ((($79.99/100)x12)/100)*6.75)
Answer:
line and point
Step-by-step explanation:
a triangle can be equally split in half, as well as with a point in the middle
Answer:
Use the two point formula: y-y¹/x-x¹ = y²-y¹/x²-x¹ to find the equation of a line through two given points.