Answer:
x=-10
Step-by-step explanation:
3x-4(2+3x)=82
3x-(4*2)+(4*3x)=82
3x-8-12x=82
-9x-8=82
-9x-8+8=82+8
-9x=90
-9x/-9=x
90/-9=-10
x=-10
First one is -6 and the second one is -3
Find slope
slope betwen 2 points (x1,y1) and (x2,y2) is (y2-y1)/(x2-x1)
so
first make denoms same
denom is 10
(4/5,1/5) turns to (8/10,2/10)
(1/2,3/2) turns to (5/10,15/10)
slope=(15/10-2/10)/(5/10-8/10)=(13/10)/(-3/10)=13/-3=-13/3
use point slope
use (4/5,1/5)
y-y1=m(x-x1)
a point is (x1,y1) and slope is m
y-1/5=-13/3(x-4/5)
expand
wait, we don't need to do that, the only one with slope -13/3 is D
answer is D
Let
C-------> the length of a circumference
C=2*pi*r-----> equation 1
we know that
in this problem-----> <span>the circumference of the foundation is 4 times the radius, increased by 114 ft
</span>so
C=4*r+114------> equation 2
(1)=(2)
2*pi*r=4*r+114------> 2*pi*r-4*r=114-----> r*[2*pi-4]=114---> r=114/[2*pi-4]
r=114/[2*pi-4]-----> 50 ft
the answer is
r=50 ft
108 you just 45x2 then 9x2 and the answer that you times before