The variable expression is x(shirt cost) + 8. The answer is x+8.
CHECK THE ATTACHED FIQURE FOR THE BRIDGE
Answer:
60 ft
Step-by-step explanation:
From the question we know that triangles ABC and EDC are in a 1:1 with this given ratio it implies that
triangles ABC and EDC are congruent then we can say
side EC = side AC
3x + 9 = 5x - 5
Then we can simplify to know value of x
3x + 14= 5x
2x = 14
x = 7
But we know that AC= 5x - 5 , then substitute value of x into it
AC = 5x + 5 = 5(7) - 5
= 35 - 5
AC= 30 ft
Also EC= 3x + 9 then substitute value of x into it
EC = 3x + 9 = 3(7) + 9
= 21 + 9
EC= 30 ft
Then the the distance between the top and bottom of the bridge, in feet, = EC+AC
= 30 + 30 = 60 ft
cos (2x) = cos x
2 cos^2 x -1 = cos x using the double angle formula
2 cos ^2 x -cos x -1 =0
factor
(2 cos x+1) ( cos x -1) = 0
using the zero product property
2 cos x+1 =0 cos x -1 =0
2 cos x = -1 cos x =1
cos x = -1/2 cos x=1
taking the arccos of each side
arccos cos x = arccos (-1/2) arccos cos x = arccos 1
x = 120 degrees x=-120 degrees x=0
remember you get 2 values ( 2nd and 3rd quadrant)
these are the principal values
now we need to add 360
x = 120+ 360n x=-120+ 360n x = 0 + 360n where n is an integer
Using the midline property;





Same question
x+y=30
x is 1/5 of y
x=y/5
subsitute
y/5+y=30
multily both sidse by 5
y+5y=150
add
6y=150
divide both sides by 6
y=25
subsitute
x=y/5
x=25/5
x=5
the numbers are 5 and 25