Alright so I got A=4, B=5 and C=9
A B C
+ A C B
----------
C B A
459
+ 495
--------
954
Answer: x = 2
Step-by-step explanation:
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Replace y in the first equation by the value of y in the second equation.
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<h3>
Answer: 24 yards, choice D</h3>
There are 4 sides to this figure (trapezoid). The left slanted side and the right most vertical side, combined with the top and bottom horizontal sides, will get us the perimeter.
left slanted side = 5 yards
right most vertical side = 4 yards (see note below)
bottom side = 9 yards
top side = 6 yards
Add up the four sides mentioned: 5+4+9+6 = 9+15 = 24
note: the rectangle has opposite sides that are the same length. While the right most side isn't labeled, it is the same length as the left side of the rectangle, so both are 4 yards long.
Another thing I should probably mention is that we do not add in the interior 4 yard side. The perimeter is only the outer or exterior sides we care about. Think of it like we're trying to fence around some property lot and we don't want to subdivide the property up. Finding the perimeter will help us find the amount of fencing needed to surround the property.
Te x intercepts are where the graph crosses the x axis or wher y=0
the y intercept is where the graph crosses the y axis or where x=0
to find vertex, here is a hack
the x coordinate of the vertex for an equation in form ax^b+bx+c=y is -b/2a
so
y=3x^2+12x+7
-b/2a=-12/2(3)=-12/6=-2
sub that back
y=3(-2)^2+12(-2)+7
y=3(3)-24+7
y=9-17
y=-8
vertex is (-2,-8)
intercepts
x intercept is where y=0
0=3x^2+12x+7
using quadratic formula
x=(-6-√15)/3 and (-6+√15)/3
xints at ((-6-√15)/3,0) and ((-6+√15)/3,0)
yint is where x=0
set x=0
y=7
yint is at y=7 or (0,7)
vertex at (-2,-8)
xints at x=
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and
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or at the points
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and
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yint at y=7 or at (7,0)