Answer:
5+23
Step-by-step explanation:
increased by is another word for add
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>
Combining like terms, we have
Answer:
SteLet a = short leg of the right triangle, b = the longer leg, and c = the hypotenuse.
The longer leg of a right triangle is 4inches longer than the shorter leg: b = a + 4
The hypotenuse is 8inches longer than the shorter leg: c = a + 8
Use the Pythagorean Theorem:
a2 + b2 = c2
a2 + (a+4)2 = (a+8)2
a2 + a2 + 8a + 16 = a2 + 16a + 64
a2 - 8a - 48 = 0
Factors to:
(a-12)(a+4) = 0
a = 12, -4
Since we can't have a side of -4, a = 12
Shorter Leg = 12 inches
Longer Leg = 12 + 4 = 16 inches
Hypotenuse = 12 + 8 = 20 inches
The anwser is D and I’m sure of it
